Integral inverter and solar cell module including the same

ABSTRACT

An integral inverter, usable with a solar cell module comprising a solar cell panel, can include a terminal for inputting a DC power from the solar cell panel; a bypass diode electrically connected to the terminal; an inverter member including a direct current (DC)-alternating current (AC) inverter electrically connected to the bypass diode; a case to integrate at least one of the terminal and the bypass diode with the DC-AC inverter located therein, and attached to a back surface of the solar cell panel using an adhesive; and an AC cable for outputting AC power from the case.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation of U.S. application Ser. No.14/478,892, filed on Sep. 5, 2014 (now U.S. Pat. No. 9,735,699, issuedAug. 15, 2017), which claims priority under 35 U.S.C. § 119(a) to KoreanPatent Applications Nos. 10-2014-0005263, filed on Jan. 15, 2014 and10-2014-0009834 filed on Jan. 27, 2014 in the Korean IntellectualProperty Office, the disclosures of all of these applications areincorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention

Embodiments of the invention relate to an integral inverter and a solarcell module including the same, and more particularly to an integralinverter having an improved structure and a solar cell module includingthe same.

Description of the Related Art

Recently, due to depletion of existing energy resources, such as oil andcoal, interest in alternative sources of energy to replace the existingenergy resources is increasing. Most of all, solar cells are popularnext generation cells to convert sunlight into electrical energy.

A solar cell panel having solar cells is connected to a junction boxand, in turn, the junction box is connected to a direct current(DC)-alternating current (AC) inverter via a direct current output cableprotruding from the junction box. More specifically, the DC-AC inverterconverts direct current voltage or direct current, transmitted via apositive output cable and a negative output cable protruding from thejunction box, into alternating current voltage or alternating current.The alternating current voltage or alternating current, generated by theDC-AC inverter, is transmitted to another solar cell module via an ACoutput cable, or transmitted to a power grid or the like.

In this instance, since the junction box and the DC-AC inverter must beseparately manufactured and installed (for example, separatelymanufactured and installed in different cases), an installation spaceand installation time are increased upon application thereof to a solarcell module. In addition, since it is necessary to position DC outputcables (i.e. two output cables) between the junction box and the DC-ACinverter for connection therebetween, an additional installation spaceand installation time are needed. In particular, these output cables arebulky and heavy, thus causing difficulty in installation. For thisreason, an installation process of the junction box and the DC-ACinverter has very low productivity. In addition, the two output cablesinterconnecting the junction box and the DC-AC inverter may be shaken orseparated from the junction box and the DC-AC inverter duringtransportation and when in use, thus causing several problems, such as,for example, damage to the solar cell panel due to collision with thesolar cell panel.

SUMMARY OF THE INVENTION

Therefore, the embodiments of the invention have been made in view ofthe above problems, and it is an object of the embodiment of theinvention to provide an integral inverter which is capable of improvingproductivity of an assembly process of a solar cell module and improvingstructural stability of the solar cell module and a solar cell moduleincluding the same.

In accordance with one aspect of the embodiment of the invention, theabove and other objects can be accomplished by the provision of anintegral inverter usable with a solar cell module comprising a solarcell panel, the integral inverter including a terminal connected to thesolar cell panel, a bypass diode electrically connected to the terminal,an inverter member including a direct current (DC)-alternating current(AC) inverter electrically connected to the bypass diode and a caseconfigured to integrate at least one of the terminal and the bypassdiode with the DC-AC inverter located therein.

In accordance with another aspect of the embodiment of the invention,there is provided a solar cell module including a solar cell panelincluding a solar cell and a ribbon extending from the solar cell and anintegral inverter including a terminal connected to the ribbon, a bypassdiode electrically connected to the terminal, an inverter memberincluding a direct current (DC)-alternating current (AC) inverterelectrically connected to the bypass diode and a case configured tointegrate at least one of the terminal and the bypass diode with theDC-AC inverter located therein, wherein the case includes a firstthrough-hole for connection of the ribbon and the terminal and a secondthrough-hole for connection with the DC-AC inverter and an externalelement.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of theembodiment of the invention will be more clearly understood from thefollowing detailed description taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a front perspective view showing a solar cell module includingan integral inverter according to an embodiment of the invention;

FIG. 2 is a rear perspective view showing the solar cell module of FIG.1;

FIG. 3 is a sectional view taken along line of FIG. 1;

FIG. 4 is an enlarged exploded perspective view of portion A of FIG. 2;

FIG. 5 is an enlarged exploded perspective view of portion A of FIG. 2showing a surface of an integral inverter adjacent to a solar cell panelseparated from the integral inverter;

FIG. 6 is a perspective view showing some parts of the integral invertershown in FIG. 1;

FIG. 7 is a sectional view taken along line VII-VII of FIG. 5 showingdifferent examples in (a) and (b);

FIG. 8 is a perspective view showing various alternative embodimentswhich may be applied to the integral inverter of the solar cell moduleshown in FIG. 1;

FIG. 9 is a perspective view showing terminals which may be applied tothe integral inverter of the solar cell module shown in FIG. 1 andribbons connected to the terminals;

FIG. 10 is an example block diagram showing the terminals of the solarcell module shown in FIG. 1 and the integral inverter;

FIG. 11 is an example circuit diagram of the integral inverter shown inFIG. 10;

FIG. 12A is a sectional view taken along line A-A of FIG. 4;

FIG. 12B is a sectional view taken along line B-B of FIG. 4;

FIG. 12C is a sectional view taken along line C-C of FIG. 4; and

FIGS. 13A to 13D are views showing various examples of a contact portionformed by a third fastening member shown in FIG. 12C.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the embodiments of theinvention, examples of which are illustrated in the accompanyingdrawings. However, it will be understood that the invention should notbe limited to the embodiments and may be modified in various ways.

In the drawings, to clearly and briefly explain the embodiments of theinvention, illustration of elements having no connection with thedescription is omitted, and the same or extremely similar elements aredesignated by the same reference numerals throughout the specification.In addition, in the drawings, for more clear explanation, the dimensionsof elements, such as thickness, width, and the like, are exaggerated orreduced, and thus the thickness, width, and the like of the embodimentof the invention are not limited to the illustration of the drawings.

In the entire specification, when an element is referred to as“including” another element, the element should not be understood asexcluding other elements so long as there is no special conflictingdescription, and the element may include at least one other element. Inaddition, it will be understood that, when an element such as a layer,film, region or substrate is referred to as being “on” another element,it can be directly on the other element or intervening elements may alsobe present. On the other hand, when an element such as a layer, film,region or substrate is referred to as being “directly on” anotherelement, this means that there are no intervening elements therebetween.

Hereinafter, an integral inverter and a solar cell module including thesame according to embodiments of the invention will be described indetail with reference to the accompanying drawings.

FIG. 1 is a front perspective view showing a solar cell module includingan integral inverter according to an embodiment of the invention andFIG. 2 is a rear perspective view showing the solar cell module ofFIG. 1. In addition, FIG. 3 is a sectional view taken along line III-IIIof FIG. 1.

With reference to FIGS. 1 to 3, the solar cell module, designated byreference numeral 100, according to the embodiment of the inventionincludes a solar cell panel 10 having solar cells 12 and an integralinverter 30 mounted on and connected to the solar cell panel 10. Thesolar cell module 100 may further include a frame 20 configured to fixan outer rim portion of the solar cell panel 10. A sealing member may belocated between the solar cell panel 10 and the frame 20 to hermeticallyseal and attach the solar cell panel 10 and the frame 20 to each other.This will be described below in more detail.

The solar cell panel 10 includes one or more solar cells 12. Inaddition, the solar cell panel 10 may include a sealing layer 14surrounding the solar cells 12 to hermetically seal the same, a frontsubstrate 16 disposed on one surface of the sealing layer 14 at thefront of the solar cells 12 and a back substrate 18 disposed on theother surface of the sealing layer 14 at the back of the solar cells 12.

In one example, the solar cell panel 10 may include the solar cells 12,a semiconductor substrate (for example, a single crystal semiconductorsubstrate, more particularly, a single crystal silicon wafer), first andsecond conductive areas formed on or above the semiconductor substrate,the first and second conductive areas having opposite conductivities,and first and second electrodes connected respectively to the first andsecond conductive areas. Here, the semiconductor substrate may have alow-density p-type or n-type dopant, and one of the first and secondconductive areas may have a p-type dopant and the other conductive areamay have an n-type dopant. In addition, the first or second conductivearea may be a doping area formed by doping a portion of thesemiconductor substrate with a dopant and may be a semiconductor layerseparately formed above the semiconductor substrate and doped with adopant. In addition, the solar cells 12 may be arranged in a line toform a solar cell string in such a way that the first electrode of onesolar cell 12 is connected to the second electrode of anotherneighboring solar cell 12 by a ribbon 122 or the like. Various otherknown structures may be applied to a structure of the solar cells 12, aconnection structure of the solar cells 12 and the like.

As described above, the embodiment of the invention exemplifies that thesolar cells 12 are single crystal silicon semiconductor solar cells.However, the embodiment of the invention is not limited thereto and thesolar cells 12 may be selected from among various other structures ofsolar cells, such as thin film solar cells, fuel sensitive solar cells,tandem solar cells, composite semiconductor solar cells and the like. Inaddition, although the embodiment of the invention exemplifies provisionof the solar cells 12, a single solar cell 12 may be provided.

The sealing layer 14 may include a first sealing layer 14 a locatedbetween the solar cells 12 and the front substrate 16 and a secondsealing layer 14 b located between the solar cells 12 and the backsubstrate 18, the first sealing layer 14 a and the second sealing layer14 b being bonded to each other. The sealing layer 14 surrounds andhermetically seals the solar cells 12, thereby blocking moisture oroxygen that may have a negative effect on the solar cells 12. Inaddition, constituent components of the solar cell module 100 (i.e. thefront substrate 16, the solar cells 12 and the back substrate 18) arechemically coupled to one another. Through implementation of alamination process of stacking the back substrate 18, the second sealinglayer 14 b, the solar cells 12 or the solar cell string, the firstsealing layer 14 a and the front substrate 16 one above another in thissequence and, thereafter, bonding the same to one another by applyingheat and/or pressure thereto, all of the aforementioned constituentcomponents may be integrated with one another.

The first sealing layer 14 a and the second sealing layer 14 b may beformed of ethylene vinyl acetate (EVA) copolymer resin, polyvinylbutyral, silicone resin, ester-based resin, olefin-based resin or thelike. In this instance, the first sealing layer 14 a and the secondsealing layer 14 b may be formed of the same material, or may be formedof different materials. However, the embodiment of the invention is notlimited thereto. Thus, the first and second sealing layers 14 a and 14 bmay be formed of one or more of various other materials via variousother methods rather than the aforementioned lamination process.

The front substrate 16 is disposed on the first sealing layer 14 a toform a front surface of the solar cell panel 10. The front substrate 16may be formed of a material that has sufficient strength to protect thesolar cells 12 from external shock and the like and light transmittanceto transmit light such as sunlight and the like. In one example, thefront substrate 16 may be a glass substrate. In this instance, the frontsubstrate 16 may be a tempered glass substrate to achieve enhancedstrength, and various other alterations in which the front substrate 16additionally comprises various other materials to achieve variousenhanced properties are possible. Alternatively, the front substrate 16may be a sheet or film formed of a resin or the like. That is, theembodiment of the invention is not limited to these constituentmaterials of the front substrate 16 and the front substrate 16 may beformed of various other materials.

The back substrate 18 is a protective layer disposed on the secondsealing layer 14 b to protect the solar cells 12 at the back of thesolar cells 12. The back substrate 18 may have waterproofing, electricalinsulation and anti-ultraviolet functions.

The back substrate 18 may have sufficient strength to protect the solarcells 12 from external shock and the like and may function to transmitor reflect light based on a desired structure of the solar cell panel10. In one example, in a structure for introduction of light through theback substrate 18, the back substrate 18 may be formed of a lighttransmitting material. In a structure for reflection of light from theback substrate 18, the back substrate 18 may be formed of a material nottransmitting or reflecting light. In one example, the back substrate 18may take the form of a substrate such as glass, or may take the form ofa film or sheet. For example, the back substrate 18 may be aTedlar/PET/Tedlar (TPT) substrate, or may be formed of a polyvinylidenefluoride (PVDF) resin formed on at least one surface ofpolyethyleneterephthlate (PET). Poly vinylidene fluoride is a polymerhaving a structure of (CH₂CF₂)n and has double fluorine bonds, thusexhibiting excellent mechanical properties, weather-resistance andultraviolet-resistance. The embodiment of the invention is not limitedto these constituent materials of the back substrate 18.

To stably fix the solar cell panel 10 having the above-described layers,the outer rim portion of the solar cell panel 10 may be fixed to theframe 20. Although the drawing shows the entire outer rim portion of thesolar cell panel 10 as being fixed to the frame 20, the embodiment ofthe invention is not limited thereto. Thus, various other alterations,such as, for example, an alteration in which only a partial edge of thesolar cell panel 10 is fixed to the frame 20, are possible.

In the embodiment of the invention, the frame 20 may include a panelinserting part 22 into which at least a portion of the solar cell panel10 is inserted, and an extension part 24 extending outward from thepanel inserting part 22.

More specifically, the panel inserting part 22 may be comprised of afront portion 222 located at a front surface of the solar cell panel 10,a lateral portion 224 located at a lateral surface of the solar cellpanel 10, and a back portion 226 located at a back surface of the solarcell panel 10. These portions 222, 224 and 226 of the panel insertingpart 22 may be connected to one another to define a space into which theouter rim portion of the solar cell panel 10 is inserted. In oneexample, the panel inserting part 22 may be bent two times to have a“U”-shaped or “

”-shaped cross section such that an edge of the solar cell panel 10 islocated inside the panel inserting part 22. However, the embodiment ofthe invention is not limited thereto, and any one of the front portion222, the lateral portion 224 and the back portion 226 may be omitted oreach portion may be partially removed. Various other alterations arealso possible.

The extension part 24, extending rearward from the panel inserting part22, may be comprised of a first portion 242 extending rearward from thepanel inserting part 22, the first portion 242 being parallel to thelateral portion 224 (or being formed in the same plane as the lateralportion 224), and a second portion 244 bent from the first portion 242,the second portion 244 being spaced from the back surface of the solarcell panel 10 or the back portion 226 by a constant distance. The secondportion 244 may be parallel to or tilted from the back surface of thesolar cell panel 10 or the back portion 226. As such, the extension part24 may be bent one time to have an “L”-shaped or “

”-shaped cross section such that a space is defined between theextension part 24 and the back portion 226.

The extension part 24 serves to enhance the strength of the frame 20 andis configured to be fixed to a stand, a support body, a floor or thelike. The extension part 24 may have holes 24 a through which fasteningmembers, which will be fastened to the stand, the support body or thefloor, are fastened. As the fastening members or the like are fastenedthrough the second portion 244 spaced from the solar cell panel 10, itis possible to prevent damage to the solar cell panel 10 uponinstallation of the solar cell module 100 using the fastening members.

To stably fix the fastening members or the like, the second portion 244may have an area equal to or greater than an area of the back portion226 (i.e. may have a width equal to or greater than a width of the backportion 226). In addition, various known structures of fastening membersmay be used. The embodiment of the invention is not limited thereto, andthe extension part 24 may have various other shapes rather than theabove-described shape.

The frame 20 may be fixed to the solar cell panel 10 via variousmethods. In one example, the outer rim portion of the solar cell panel10 may be an elastic portion (for example, an elastic tape), and thesolar cell panel 10 may be inserted into the panel inserting part 22 ofthe frame 20 using the elastic portion thereof. However, the embodimentof the invention is not limited thereto, and various other alterations,such as, for example, an alteration in which constituent parts of theframe 20 are assembled and coupled to one another around the solar cellpanel 10, are possible.

In addition, in the embodiment of the invention, the integral inverter30 may be connected to the solar cells 12 of the solar cell panel 10. Inone example, the integral inverter 30 may be disposed on the backsurface of the solar cell panel 10 and located close to an upper endportion of the solar cell panel 10. In this instance, a thickness T1 ofthe integral inverter 30 may be equal to or less than a height H1 of theextension part 24 of the frame 20 (more particularly, a height of thefirst portion 242). Here, the height H1 of the extension part 24 may bedefined as a distance from the back surface of the solar cell panel 10to an outer surface of the second portion 244 of the extension part 24.As such, the integral inverter 30 may have a thickness required toprevent the integral inverter 30 from protruding from the outer surfaceof the second portion 244. That is, a back surface of the integralinverter 30 (i.e. a surface opposite to the solar cell panel 10) may belocated in the same plane as the outer surface of the second portion 244or may be located closer to the solar cell panel 10 than the outersurface of the second portion 244. In addition, with regard to a portionof the integral inverter 30 located inside the extension part 24, a backsurface (i.e. a surface opposite to the solar cell panel 10) of thecorresponding portion may be located in the same plane as an innersurface of the second portion 244 or may be located closer to the solarcell panel 10 than the inner surface of the second portion 244, whichmay assist the integral inverter 30 in being easily positioned insidethe extension part 24. In this way, it is possible to minimize a volumeof the solar cell module 100 and to efficiently utilize a space at theback of the solar cell panel 10. In addition, in consideration of theinstance in which a plurality of solar cell modules 100 is manufacturedand then stacked one above another upon transportation and the like, itis possible to minimize collision shock between the solar cell modules100. In the embodiment of the invention, the integral inverter 30 may becoupled to the extension part 24 of the frame 20 close to the upper endportion of the solar cell panel 10, and/or may be attached to the backsurface of the solar cell panel 10. This will be described below in moredetail.

The integral inverter 30 according to the embodiment of the invention isan integrated combination of at least a portion of a conventionaljunction box and at least a portion of a conventional inverter. Thus,the integral inverter 300 may be called a junction box integratedinverter, a bypass diode integrated inverter, an integral junction box,an inverter integrated junction box and the like. The integral inverter30 will be described below in more detail with reference to FIGS. 1 to 3and FIGS. 4 to 9.

FIG. 4 is an enlarged exploded perspective view of portion A of FIG. 2,and FIG. 5 is an enlarged exploded perspective view of portion A of FIG.2 showing a surface of the integral inverter 30 adjacent to the solarcell panel 10 separated from the integral inverter 30. FIG. 6 is aperspective view showing some parts of the integral inverter 30 shown inFIG. 1. For brief and clear illustration, a potting member 372 isomitted from FIG. 4. The potting member 372 will be described below indetail with reference to FIG. 6.

With reference to FIGS. 4 and 5, the integral inverter 30 according tothe embodiment of the invention is formed by integrating terminals 31connected to the solar cells (see reference numeral 12 in FIG. 3) (orthe solar cell panel 10) and/or bypass diodes 33 electrically connectedto the terminals 31, and an inverter member 35 electrically connected tothe bypass diodes 33 and having DC-AC inverters 352 with one another. Inthis instance, the terminals 31 may be connected to ribbons 122extending from the solar cells 12. In the embodiment of the invention, acase 39 (more specifically, a first case 49) includes a conductivematerial layer (see reference numeral 47 of FIGS. 12A to 12C) and, thus,the first case 49 has a grounding function. More specifically, theintegral inverter 30 according to the embodiment of the invention mayinclude a first ground structure 72 configured to ground the first case49 and the circuit board 37 and a second ground structure 74 configuredto ground the first case 49 and the frame 20. Assuming that the firstcase 49 includes a first case part 491 and a second case part 492coupled to each other, the integral inverter 30 may further include athird ground structure 76 configured to ground the first case part 491and the second case part 492. In one example, the first to third groundstructures 72, 74 and 76 may be acquired via fastening of first to thirdfastening members 62, 64 and 66. After description of formation of theentire integral inverter 3, the first to third ground structures 72, 74and 76 will be described below in more detail with reference to FIGS.12A to 12C and FIGS. 13A to 13D.

In the embodiment of the invention, the terminals 31 and/or the bypassdiodes 33 and the inverter member 35 are integrated with one another.

Here, integration may include all states in which two or more componentsare recognized as any one element, article, object or member when fixedto the solar cell panel 10 and/or the frame 20 during or afterinstallation. For example, integration may mean that two or morecomponents are located in the same case and integrated by the same case,may mean that two or more components are fixed to the same member byfitting or attachment and integrated by the same member, may mean thattwo or more components are formed together at the same member toconstitute a portion of the same member, and may mean that two or morecomponents are surrounded by or fixed to the same member. On the otherhand, when two or more components are connected to one another viaadditional output cables or the like, this may be difficult to beconsidered as integration. In this instance, the terminals 31, thebypass diodes 33 and the inverter member 35 may be inseparablyintegrated with one another, or may be separably integrated with oneanother to enable easy separation upon repair and replacement.

In the integral inverter 30 according to the embodiment of theinvention, the terminals 31, the bypass diodes 33 and the invertermember 35 are formed on a circuit board 37 having a circuit pattern (orwirings). As such, it can be said that the terminals 31, the bypassdiodes 33 and the inverter member 35 are integrated with one another bythe circuit board 37. In addition, as shown by example in FIG. 6, thepotting member 372 may be located to cover or surround the circuit board37. As such, it can be said that the bypass diodes 33 and the invertermember 35 are integrated with each other by the potting member 372. Inaddition, the circuit board 37 on which the terminals 31, the bypassdiodes 33 and the inverter member 35 are formed may be accommodated inthe same case 39. As such, it can be said that the terminals 31, thebypass diodes 33 and the inverter member 35 are integrated with oneanother by the same case 39.

The embodiment of the invention exemplifies that the terminals 31, thebypass diodes 33 and the inverter member 35 are integrated with oneanother by the same circuit board 37, the same potting member 372 andthe same case 39. More specifically, as the terminals 31, the bypassdiodes 33 and the inverter member 35 are arranged on the same circuitboard 37 and the potting member 372 covers the bypass diodes 33, theinverter member 35 and the circuit board 37, the terminals 31, thebypass diodes 33, the inverter member 35, the circuit board 37 and thepotting member 372 are integrated with one another to configure acircuit board unit 300. The circuit board unit 300 may be fixed in thecase 39. This may allow the terminals 31, the bypass diodes 33 and theinverter member 35 to be more firmly integrated with one another.However, the embodiment of the invention is not limited thereto and theaforementioned components may be integrated with one another in asimplified structure using at least one of various integration methods.In addition, although the embodiment of the invention exemplifies thatthe terminals 31, the bypass diodes 33 and the inverter member 35 areintegrated with one another, the embodiment of the invention is notlimited thereto. Thus, only the bypass diodes 33 and the inverter member35 may be integrated with each other and various other alterations arealso possible.

In the embodiment of the invention, the case 39 may have variousstructures and shapes to provide a space in which the terminals 31, thebypass diodes 33 and the inverter member 35, integrated with oneanother, are accommodated and to allow the solar cell panel 10 and/orthe frame 20 to be stably fixed thereto.

In one example, in the embodiment of the invention, the case 39 mayinclude a first case 49 forming an external shape or external surface ofthe case 39, the first case 49 being fixed to the solar cell panel 10and/or the frame 20, and a second case 59 located inside the first case49, the second case 59 receiving the circuit board unit 300 therein. Inthis instance, the second case 59 is separably coupled to the first case49 to allow the circuit board unit 300 received in the second case 59 tobe easily fixed to the first case 49 or to be easily separated from thefirst case 49. This will be described below in more detail.

The first case 49 will be described below in more detail with referenceto FIG. 7 as well as FIGS. 4 and 5. FIG. 7 is a sectional view takenalong line VII-VII of FIG. 5 showing different examples in (a) and (b).

In the embodiment of the invention, the first case 49 is comprised of afirst case part 491 and a second case part 492 bonded to each other toform an integral case. As such, in a state in which the first case part491 and the second case part 492 are separated from each other,insertion or removal of the circuit board unit 300 and/or the secondcase 59 into or from the first case 49 may be easily performed. Also, ina state in which the first case part 491 and the second case part 492are coupled to each other, the circuit board unit 300 and the secondcase 59 may be stably received in the first case 49.

Here, the first case part 491 may include an inner space portion 494defining an inner space by a bottom surface 4942 and lateral surfaces4944 thereof, and bonding flanges 496 extending from an upper end of theinner space portion 494, the bonding flanges 496 being parallel to orinclined relative to the bottom surface 4942. In this instance, thelateral surfaces 4944 may be formed at all edges of the bottom surface4942 such that the inner space defined in the inner space portion 494has only one open face. For example, when the bottom surface 4942 has arectangular shape, four lateral surfaces 4944 may extend respectivelyfrom four edges of the rectangular bottom surface 4942 to define arectangular parallelepiped having one open face. In one example, theinner space portion 494 may have at least five faces such that only oneface is open.

In the drawing, the bottom surface 4942 may have four straight lines andbe rounded at corners thereof where two neighboring straight lines meet.For example, the bottom surface 4942 may have an approximatelyrectangular shape and be rounded at four corners thereof. The lateralsurfaces 4944 may be formed at all of the edges of the bottom surface4942 and extend to cross the bottom surface 4942 (for example, in adirection perpendicular to the bottom surface 4942). As such, thelateral surfaces 4944 may include four planes corresponding to the fourstraight lines and four rounded surfaces located respectively betweentwo neighboring planes. This shape may provide a sufficient inner spaceand prevent a user from being injured by sharp corners. However, theembodiment of the invention is not limited thereto and shapes and thelike of the bottom surface 4942 and the lateral surfaces 4944 may bealtered in various ways.

The bonding flanges 496 may be bent from the lateral surfaces 4944 so asto extend outward. The bonding flanges 496 provide a region to which abonding member 493 is applied, thus assisting the first case part 491and the second case part 492 in being bonded to each other by thebonding member 493. In this instance, the bonding flanges 496, which arebent from the lateral surfaces 4944 so as to extend outward, open theentire inner space of the inner space portion 494, which may allow theterminals 31, the bypass diodes 33 and the inverter member 35 to beeasily inserted into or removed from the first case 49 without a risk ofbeing caught by the bonding flanges 496. The bonding flanges 496 mayinclude flat surfaces parallel to the bottom surface 4942, or flatsurfaces perpendicular to the lateral surfaces 4944. Hence, the bondingmember 493 may be stably applied to the bonding flanges 496. However,the embodiment of the invention is not limited thereto.

In the embodiment of the invention, when viewing the bonding flanges 496extending from ends of the lateral surfaces 4944 in plan, the bondingflanges 496 are successively formed to close the inner space defined bythe inner space portion 494. Here, the bonding flanges 496 may includeflat surfaces so as to be located in the same plane. Hence, the firstcase part 491 and the second case part 492 may be wholly bonded to eachother by the bonding member 493 applied to the bonding flanges 496,which may maintain high hermetic sealing efficiency of the interior ofthe first case 49. In this instance, the bonding flanges 496 may have aconsistent width to ensure even application of the bonding member 493,thus allowing the first case part 491 and the second case part 492 to bestably bonded to each other. In addition, when repair, replacement orthe like is needed, a cutting tool (for example, a knife or the like)may be introduced into a gap between the bonding flange 496 and thesecond case part 492 and moved along the bonding flanges 496 to cut thebonding member 493, which enables easy separation of the first case part491 and the second case part 492. That is, the first case part 491 andthe second case part 492 may be easily separated from each other bymoving the cutting tool along the flat surfaces of the bonding flanges496.

In the embodiment of the invention, the second case part 492 may takethe form of a plate that covers the open face of the inner space portion494 and has an edge profile matching outer edges of the bonding flanges496.

In this instance, as shown by example in (a) of FIG. 7, the second casepart 492 may include a flat inner portion 497 parallel to the bottomsurface 4942 and an inclined outer portion 499 located at the outer sideof the inner portion 497 to extend far away from the first case part491. A portion of the outer portion 499 overlapping the correspondingbonding flange 496 is bonded to the bonding flange 496 by the bondingmember 493.

As a result of forming the inclined outer portion 499, a boundary line(or a boundary portion) that is visible to the naked eye or detectableby equipment is formed between the inner portion 497 and the outerportion 499. Thus, positions of the first case part 491 and the secondcase part 492 may be roughly aligned by positioning the outer portion499 over the bonding flange 496 or by positioning the outer portion 499so as not to deviate from the bonding flange 496. In this instance, theinner portion 497 may have a smaller area than an area of the bottomsurface 4942. For example, a width W2 of the outer portion 499 may begreater than a width W1 of the bonding flange 496. Hence, positions ofthe first case part 491 and the second case part 492 may be more easilyroughly aligned by positioning the boundary line between the innerportion 497 and the outer portion 499 inside the bonding flange 496(i.e. in the inner space). The boundary line between the inner portion497 and the outer portion 499 or the inner or outer portion 497 or 499may serve as a guide, alignment mark or the like.

In addition, as a result of the outer portion 499 being inclined awayfrom the inner portion 497, as shown by example in (a) of FIG. 7, adistance between the bonding flange 496 and the outer portion 499 (i.e.a thickness of the bonding member 493 located between the bonding flange496 and the outer portion 499) is slightly greater at an outer edge ofthe bonding flange 496 than at an inner edge of the bonding flange 496.Hence, since a distance between the first case part 491 and the secondcase part 492 is greater at the outer edge of the bonding flange 496,the cutting tool may be easily introduced into the gap between thebonding flange 4976 and the outer portion 499 to cut the bonding member493 upon separation of the first case part 491 and the second case part492.

However, the embodiment of the invention is not limited thereto and theinner portion 497 and the outer portion 499 may have various othershapes. For example, as shown by example in (b) of FIG. 7, the innerportion 497 and the outer portion 499 may be stepped from each other bybending. In this instance, the inner portion 497 may protrude from theouter portion 499 toward the first case part 491 and the outer portion499 may be located farther from the first case part 491 than the innerportion 497. Hence, the inner portion 497 may be located inside thefirst case part 491 and the outer portion 499 may be seated on thecorresponding bonding flange 496, which may improve fixing stability ofthe first case part 491 and the second case part 492.

In addition, the embodiment of the invention exemplifies that the secondcase part 492 includes the inner portion 497 and the outer portion 499.The embodiment of the invention is not limited thereto and the secondcase part 492 may include a first portion and a second portion havingdifferent shapes and formed of different materials and the like. Assuch, a boundary line between the first portion and the second portionor the first or second portion may serve as a guide, alignment mark orthe like. Alternatively, one of the first and second portions may beused to fix the first and second case parts 491 and 492 to each otherusing the bonding member 493 applied thereto, thereby serving to improvefixing stability.

The bonding member 493, which is located between each bonding flange 496of the first case part 491 and the outer portion 499 of the second casepart 492, serves to bond and seal the first case part 491 and the secondcase part 492, thereby preventing introduction of impurities,contaminants and the like from the outside and improving sealing andwaterproofing performance. The bonding member 493 may be formed of anyone of various materials having bonding and/or sealing properties and,for example, may be a sealant.

Although the embodiment of the invention exemplifies that the first casepart 491 and the second case part 492 are fixed to each other by thebonding member 493, the embodiment of the invention is not limitedthereto. That is, the first case part 491 and the second case part 492may be fixed to each other using an elastic member, such as an O-ring orrubbery material, a latch member having a latch coupling structure, afastening member, such as a bolt, a screw and the like and various otherfixing members. In this instance, to improve sealing performance, atleast two of a bonding member, an elastic member, a latch member and afastening member may be used together. For example, when using one of anelastic member, a latch member and a fastening member with a bondingmember, both fixing stability and sealing stability may be maximized.Various other structures may also be applied.

However, the embodiment of the invention is not limited thereto and thefirst case 49 may be formed so as not to enclose the entire inner space.In addition, various alterations, such as, for example, in which thelateral surfaces of the first case part 491 are partially or whollyomitted and the second case part 492 is partially provided with lateralsurfaces, are possible. In addition, the first case 49 may consist ofthree or more parts coupled to one another and various other alterationsare also possible.

Through provision of both the first case part 491 and the second casepart 492, easy insertion and removal of internal components arepossible. In addition, through bonding of the first case part 491 andthe second case part 492 using the bonding member 493, stable sealing ofthe interior is possible, which may prevent problems due to externalmoisture and the like and stably protect internal components and thelike from external shock. However, the embodiment of the invention isnot limited thereto and the first case 49 may include at least one ofthe first case part 491 and the second case part 492. Variousalterations, such as, for example, an alteration in which the secondcase part 492 is not provided and the bonding flanges 496 of the firstcase part 491 come into close contact with the solar cell panel 10, thuscausing the solar cell panel 10 to serve as the second case part 492,are possible.

The first case 49 may include a structure for connection with the solarcells 12, an external structure (for example, another solar cell module100 or a power grid) or the like. That is, the first case 49 may have afirst through-hole 49 a through which the ribbons 122 for connectionwith the solar cells 12 pass, and a second through-hole 49 b throughwhich a single AC output cable 38 for transmission of alternatingcurrent voltage generated by the integral inverter 30 passes.

That is, the first through-hole 49 a for connection with the solar cells12 and the second through-hole 49 b for the AC output cable 38 areformed in the same first case 49. This is because the terminals 31and/or the bypass diodes 33 and the inverter member 35 are integratedwith one another. In the related art, a first through-hole forconnection with solar cells has been formed in a case of a junction boxand a second through-hole for an AC output cable has been formed in acase of an inverter in which an inverter member is located. Thus, thefirst through-hole and the second through-hole cannot be formed in thesame case. On the other hand, in the embodiment of the invention, astructure for connection with the solar cell panel 10 and the outputcable 38 used to outwardly apply alternating current voltage may beintegrated with each other by the circuit board 37.

In one example, the first through-hole 49 a may be formed in a surfaceof the first case 49 adjacent to the solar cell panel 10 (i.e. thebottom surface 4942 of the first case part 491). As such, the ribbons122, which extend from the solar cells 12 through holes formed in thesecond sealing layer 14 b and the back substrate 18, may be connected tothe terminals 31 by a shorter path. The first through-hole 49 a may be asingle hole through which the ribbons 122 (n ribbons 122) respectivelycorresponding to solar cell strings pass, or may include a plurality ofholes spaced apart from one another to correspond to the respectiveribbons 122. The drawing shows a structure in which the first case 49has a single first through-hole 49 a through which the ribbons 122 passtogether, which may ensure easier processing of the first case part 491.

The second through-hole 49 b may be formed at a position to ensure easyconnection with an external circuit. In one example, in the embodimentof the invention, the second through-hole 49 b is formed in the farthestlateral surface 4944 from the terminals 31 such that voltage appliedfrom the solar cell panel 10 to the terminals 31 is discharged outwardthrough the AC output cable 38 after sequentially passing through thebypass diodes 33 and the inverter member 35. This may provide efficientarrangement of the terminals 31, the bypass diodes 33 and the invertermember 35.

In the embodiment of the invention, the AC output cable 38 is an outputcable of the integral inverter 30 in which the terminals 31 connected tothe ribbons 122 and/or the bypass diodes 33 are arranged. Thus, thesingle AC output cable 38 may extend outward through the secondthrough-hole 49 b. Generally, the AC output cable 38 may have threeconducting wires having 3-phase voltage (current). That is, one ACoutput cable 38 has three conducting wires. The three conducting wiresof the single AC output cable 38 may be joined into one to pass throughthe single second through-hole 49 b, which may result in a simplifiedstructure. However, the embodiment of the invention is not limitedthereto and various alterations, such as, for example, an alteration inwhich the three conducting wires are discharged respectively throughdifferent second through-holes 49 b, are possible.

In the embodiment of the invention, an output cable of the integralinverter 30 in which the terminals 31 connected to the ribbons 122and/or the bypass diodes 33 are arranged is the AC output cable 38 andthere is no DC output cable. This is because the terminals 31 and/or thebypass diodes 33 and the inverter member 35 are integrated with oneanother. In the related art, since direct current voltage or directcurrent is discharged from a junction box in which terminals and bypassdiodes are arranged, there are two DC output cables including a positiveoutput cable and a negative output cable.

The first case 49 may further have a fastener 49 c for coupling with theframe 20. The fastener 49 c is a part that is coupled to the frame 20via fastening members 62. In the embodiment of the invention, thefastener 49 c may be integrally formed with the first case part 491 orthe second case part 492 so as to extend therefrom. As such, the firstcase 49 having the fastener 49 c may be formed by the same process,which may improve productivity.

The fastener 49 c may extend from a portion of the first case 49adjacent to the frame 20 (i.e. an upper end portion in the drawing) andcome into contact with at least one surface of the frame 20 (moreparticularly, the second portion 244 of the frame 20). As the fastener49 c and the second portion 244 are provided with fastening holes 490 cand 244 c and the fastening members 64 (for example, screws) arefastened through the fastening holes 490 c and 244 c, the first case 49may be fixed to the frame 20. In this way, the first case 49 and theframe 20 may be firmly fixed to each other via a simplified structure.In addition, the second ground structure 74 may be configured byfastening the second fastening members 64 through the fastening holes490 c and 244 c formed in the fastener 49 c and the second portion 244.The second ground structure 74 will be described below in more detail.

In one example, in the embodiment of the invention, the fastener 49 cincludes a fastening portion 491 c fastened to the frame 20. Inaddition, the fastener 49 c may further include extension portions 492c, 493 c and 494 c connected from the fastening portion 491 c to theinner space portion 494. The extension portions 492 c, 493 c and 494 cmay include a first extension portion 492 c bent from the fasteningportion 491 c to extend toward the solar cell panel 10, a secondextension portion 493 c bent from the first extension portion 492 c toextend in parallel to the solar cell panel 10, and a third extensionportion 494 c bent from the second extension portion 493 c to extend tothe back of the solar cell panel 10 and to the bonding flange 496.

The fastening portion 491 c may be positioned to come into contact (orclose contact) with the second portion 244 of the frame 20. In oneexample, the fastening portion 491 c may be positioned to come intoclose contact with an inner surface of the second portion 244 (i.e. asurface facing the back portion 226 or the solar cell panel 10) suchthat the fastener 49 c is positioned in a space inside the extensionpart 24. In this instance, fastening holes 224 c and 490 c are formed incorresponding positions of the second portion 244 and the fasteningportion 491 c coming into close contact with the inner surface of thesecond portion 244. In addition, holding pieces 490 d may be formed atlateral edges of the fastening portion 491 c so as to pass throughholding holes 244 d of the second portion 244. Hence, after the fastener49 c is set to a desired position by fitting the holding pieces 490 d ofthe fastening portion 491 c into the holding holes 244 d of the secondportion 244, the fastener 49 c and the second portion 244 may be fixedto each other via the fastening members 62. In the embodiment of theinvention, the holding pieces 490 d may be protrusions that protrude ina direction opposite to the solar cell panel 10 to pass through thesecond portion 244, and the holding holes 244 d may be formed atpositions corresponding to the holding pieces 490 d. In this way,positions of the fastener 49 c and the second portion 244 may be easilyaligned using a simplified structure. In addition, as the holding pieces490 d are formed respectively at both lateral edges of the fasteningportion 491 c and the two holding holes 244 d are formed to correspondto the respective holding pieces 490 d, alignment performance may beenhanced. However, the embodiment of the invention is not limitedthereto. Thus, various alterations with regard to a coupling structureof the fastener 49 c and the frame 20, a coupling structure of theholding pieces 490 d and the holding holes 244 d, shapes, positions andthe number of these components are possible.

The first extension portion 492 c may come into contact (or closecontact) with the frame 20 (more accurately, the first portion 242).More specifically, the first extension portion 492 c may come intocontact (or close contact) with an inner surface of the first portion242. As such, the fastener 49 c and the frame 20 may be more firmlyfixed to each other.

The second extension portion 493 c may be spaced from the solar cellpanel 10 or the frame 20. In the embodiment of the invention, the firstcase part 491 and the second case part 492 may be fastened to each othervia third fastening members 66 under the use of the second extensionportion 493 c. The reason why the second extension portion 493 c isspaced from the solar cell panel 10 is to ensure easier coupling of thefirst case part 491 and the second case part 492. However, theembodiment of the invention is not limited thereto and the first casepart 491 and the second case part 492 may be bonded to each other usingonly the bonding member 493 without an additional fastening method, ormay be fastened to each other at different positions. In this instance,the second extension portion 493 c may come into close contact with theback surface of the solar cell panel 10 or the back portion 226 of theframe 20 to improve fixing stability. Various other alterations are alsopossible.

At least one through-hole 490 f may be continuously formed in the firstextension portion 492 c and the second extension portion 493 c to ensureeasier processing of the fastener 49 c that is subjected to bendingplural times. To improve ease of processing, a plurality ofthrough-holes 490 f may be formed although the embodiment of theinvention is not limited thereto. In addition, shapes, sizes and thelike of the through-holes 490 f are not greatly limited.

When the fastener 49 c is bent plural times to include the first tothird extension portions 492 c, 493 c and 494 c as well as the fasteningportion 491 c, the fastener 49 c may serve as a reinforcement member,thus having high strength. Thereby, a portion of the fastener 49 ccoupled to the frame 20 may achieve sufficient strength.

A bracket may be provided to cover the front side of the fastener 49 c(i.e. at least a gap between the fastening portion 491 c and the thirdextension portion 494 c) so as to improve an external appearance of thefastener 49 c. The bracket may be separably fixed to the fastener 49 cvia a latch structure or the like. However, the embodiment of theinvention is not limited thereto and the bracket may be fixed viavarious other methods.

A portion of the second case part 492 corresponding to the fastener 49 cmay be provided with a fixture 49 d to be fixed to the fastener 49 c.The fixture 49 d may include a first fixing portion 491 d configured tocome into contact (or close contact) with the second extension portion493 c and a second fixing portion 492 d bent from the fastening portion491 c to extend and be connected to the outer portion 499. The firstfixing portion 491 d and the second extension portion 493 c may havefastening holes 490 e and 490 g formed at corresponding positions. Asthe third fastening members 66 are fastened through the fastening holes490 e and 490 g, the first case part 491 and the second case part 492may be more firmly coupled to each other. In this way, the first case 49may achieve an improved hermetic sealing structure and fixing structure.In addition, in the embodiment of the invention, the third groundstructure 76 may be configured by fastening the third fastening members66 through the fastener 49 c and the fixture 49 d. This will bedescribed below in more detail.

In the embodiment of the invention, the first case 49 is fixed orattached to the solar cell panel 10. That is, in the embodiment of theinvention, an adhesive member 69 may be located at a bottom surface ofthe first case 49 adjacent to the solar cell panel 10 (for example, thebottom surface 4942 of the first case part 491) to stably fix the solarcell panel 10 to the first case 49 (or the integral inverter 30) and toachieve a good hermetic seal and waterproofing performance.

More specifically, the adhesive member 69 may be configured to define aclosed space therein while surrounding the first through-hole 49 a ofthe first case 49 when viewed in plan. As such, the adhesive member 69may serve to isolate a space between the solar cell panel 10 and thefirst case 49 defined inside thereof from an external space whileallowing the ribbons 122 to be inserted into the first case 49 throughthe first through-hole 49 a of the first case 49. In this way, theadhesive member 69 may hermetically seal the first case 49 having thefirst through-hole 49 a.

As described above, the first case 49 has the first through-hole 49 aand the second through-hole 49 b. The second through-hole 49 baccommodates the AC output cable 38 and, thus, remains in a hermeticallysealed state, whereas the first through-hole 49 a must be open to ensuresmooth passage of the ribbons 122. Therefore, external substances,impurities, moisture and the like may be introduced into the first case49 through the first through-hole 49 a when the adhesive member 69 isnot provided. Therefore, in the embodiment of the invention, theadhesive member 69 surrounding the space opened by the firstthrough-hole 49 a may serve to prevent the interior of the first case 49from communicating with the outside through the first through-hole 49 a.This may improve hermetic sealing and waterproofing performance of thefirst case 49. In addition, the adhesive member 69 may fix the firstcase 49 to the solar cell panel 10, thus improving fixing stability.

In one example, the adhesive member 69 may have a circular shape, apolygonal shape or the like when viewed in plan. As shown in thedrawing, the first through-hole 49 a may have a rectangular shape andthe adhesive member 69 may have a rectangular shape. However, theembodiment of the invention is not limited thereto and the adhesivemember 69 may have various other structures and shapes to preventcommunication between the first through-hole 49 a and the interior ofthe first case 49.

In the embodiment of the invention, the integral inverter 30 having thefirst through-hole 49 a for connection between the ribbons 122 and theterminals 31 is provided with the adhesive member 69, thus achievingimproved hermetic sealing performance. On the other hand, conventionalinverters do not have the above-described first through-hole forconnection with the solar cells 12.

The adhesive member 69 may be formed of any one of various materialshaving good adhesive and hermetic sealing properties and the like. Inone example, the adhesive member 69 may be a sealant. However, theembodiment of the invention is not limited thereto. Thus, variousalterations, such as, for example, an alteration in which the adhesivemember 69 is a structure formed of a resin, a metal or the like tothermally attach the first case 49 and the solar cell panel 10 to eachother, are possible.

The above-described first case 49 may have a fixed external shape orexternal surface and may comprise various materials capable ofprotecting various elements, articles, members and the like arrangedtherein. In one example, the first case 49 may include a conductivematerial layer 47 to achieve enhanced structural stability and may beused for grounding and the like. For example, the conductive materiallayer 47 of the first case 49 may be a metal layer. In this instance,when the first case 49 is formed of a surface treated metal (or coatedmetal), the conductive material layer 47 may be located inside the firstcase 49 and a surface treated layer having electrical insulationproperties (see reference numeral 48 of FIGS. 12A to 12C) may be locatedaround the conductive material layer 47 to surround the conductivematerial layer 47. As such, the surface treated layer 48 formed of anelectrically insulating material may achieve improved wear-resistanceand external appearance and the inner conductive material layer 47 maybe used for grounding and the like. The ground structure will bedescribed below in more detail.

In one example, the first case 49 may be formed of an anodized metal(for example, anodized aluminum). As such, the first case 49 may includethe conductive material layer 47 comprising aluminum and the surfacetreated layer 48 comprising aluminum oxide. In addition, upon surfacetreatment (for example, anodization), the first case 49 may be coloredto improve external appearance. For example, the first case 49 may becolored black, brown, silver or the like.

In the embodiment of the invention, the second case 59 may be locatedinside the first case 49. The second case 59 will be described below inmore detail with reference to FIGS. 4 to 6. FIG. 6 shows the first casepart 491 of the first case 49, an inner space portion 594 of the secondcase 59, and the circuit board unit 300 located in the inner spaceportion 594 and the like.

The second case 59 serves to support or receive the circuit board unit300 such that the circuit board unit 300 is easily separable from thefirst case 49. Thus, when repair, replacement or the like is needed, thecircuit board unit 300 may be separated from the first case 49 as thefirst case 49 is opened and then the second case 59 is separated fromthe first case 49. In addition, when replacement is needed, the secondcase 59 in which the terminals 31, the bypass diodes 33, the invertermember 35 and the like are supported or received may be simply replacedas the second case 59 is inserted into the first case 49.

The second case 59 may further serve as a receptacle for reception ofthe potting member 372 that encloses the terminals 31, the bypass diodes33, the inverter member 35 and the like. That is, as the potting member372 having fluidity is injected or poured into the second case 59 andthen solidified by drying, thermal treatment or the like in a state inwhich the terminals 31, the bypass diodes 33, the inverter member 35 andthe like are arranged in the second case 59, the second case 59, theterminals 31, the bypass diodes 33, the inverter member 35 and the likemay be integrated with one another. This may simplify an applicationprocess of the potting member 372 and provide a more firmly integratedstructure of the bypass diodes 33 and the inverter member 35.

The second case 59 may have any one of various structures to support orreceive the terminals 31, the bypass diodes 33, the inverter member 35and the like.

In one example, in the embodiment of the invention, the second case 59may include the inner space portion 594 having a bottom surface 5942located at a portion of the first case 49 except for the firstthrough-hole 49 a and lateral surfaces 5944 extending from the bottomsurface 5942. When the lateral surfaces 5944 are formed at all edges ofthe bottom surface 5942, the second case 59 may more effectively performthe role of the receptacle for the potting member 372. However, theembodiment of the invention is not limited thereto and the inner spaceportion 594 may have only the bottom surface 5942 so as not to define aninner space. In addition, the second case 59 may include a cover portion592 configured to cover an upper surface of the inner space portion 594.The cover portion 592 is configured so as not to cover the firstthrough-hole 49 a and the terminals 31, i.e. to expose the firstthrough-hole 49 a and the terminals 31, which may ensure easierconnection between the ribbons 122 and the terminals 31. However, theembodiment of the invention is not limited thereto and the cover portion592 may be omitted.

In addition, in some cases (for example, in the instance in which thefirst case 49 is conductive), the second case 59 may serve to maintainan electrical insulation distance for a circuit pattern of the circuitboard 37 and the like. In this instance, the second case 59 may beformed of an electrically insulating material to maintain an electricalinsulation distance between the first case 49 and the circuit board 37.However, the embodiment of the invention is not limited thereto. Thatis, even when the first case 49 is conductive, the second case 59 may beformed of a conductive material. Alternatively, the second case 59 maybe omitted. When the second case 59 does not satisfy the requirement ofelectrical insulation distance or is omitted, another structure tosatisfy the requirement of electrical insulation distance may beprovided. This will be described below in more detail with reference toFIG. 8.

FIG. 8 is a perspective view showing various alternative embodimentswhich may be applied to the integral inverter 30 of the solar cellmodule 100 shown in FIG. 1. In FIG. 8, for clear and simplifieddescription, only components required for description are shown andillustration of other components is omitted.

For example, as shown by example in (a) of FIG. 8, the terminals 31, thebypass diodes 33, the inverter member 35, the circuit board 37 and thelike may be wholly enclosed by the potting member 372 or an additionalelectrically insulating material. Then, the circuit board unit 300 andthe like, enclosed by the potting member 372 or an additionalelectrically insulating material, may be located in the first case 49without the second case 59. As such, the potting member 372 or theelectrically insulating material may satisfy an electrical insulationdistance.

In another example, as shown by example in (b) of FIG. 8, spacers 82 maybe arranged in the first case 49 (for example, at an inner surface ofthe first case part 491). The spacers 82 serve to maintain a constantdistance between the first case 49 and the second case 59 or between thefirst case 49 and the circuit board 37 and are formed of an electricallyinsulating material. As such, the spacers 82 satisfy an electricalinsulation distance. A shape, arrangement and the like of the spacers 82may be altered in various ways.

In a further example, as shown by example in (c) of FIG. 8, insulationpads 84 may be attached to some positions of an inner surface of thefirst case 49 (for example, an inner surface of the first case part491). Alternatively, as shown by example in (d) of FIG. 8, an insulationsheet 86 may be located between the first case 49 and the second case 59or between the first case 49 and the circuit board 37. Alternatively,the first case 49 may be coated with an electrically insulating materialor be subjected by surface treatment to satisfy an electrical insulationdistance. Various other methods, structures and the like may also beapplied.

The second case 59, the insulation pads 84, the insulation sheet 84 orthe like, which is located in the first case 49 at a position betweenthe first case 49 and the circuit board unit 300, may be called an innermember. Various structures, shapes and the like except for theabove-described examples may be applied to the inner member.

With reference again to FIGS. 4 to 6, although the drawings show thatthe second case 59 does not overlap the first through-hole 49 a by wayof example, the embodiment of the invention is not limited thereto andan opening corresponding to the first through-hole 49 a may be formed inthe second case 59. In addition, various other structures to allow theribbons 122, having passed through the first through-hole 49 a, to beconnected to the terminals 31 through the second case 59, may be appliedto the second case 59.

The first case 49 and the second case 59 may be separably coupled toeach other via various structures. In one example, in the embodiment ofthe invention, first clinching nuts (pem nuts) 490 h may be located atthe first case 49 and fastening holes 590 f may be formed in the secondcase 59 at positions corresponding to the first clinching nuts 490 h.

More specifically, the first clinching nuts 490 h and the fasteningholes 590 f may be located respectively at both sides of the terminals31 connected to the ribbons 122 (or at both sides of the firstthrough-hole 49 a) to allow the first case 49 and the second case 59 tobe coupled to each other at a portion where the ribbons 122 havingpassed through the first through-hole 49 a are connected to theterminals 31, which may minimize generation of a clearance at thecorresponding portion. This enables stable coupling of the ribbons 122.In this instance, fastening portions 590 h provided with the fasteningholes 590 f may extend outward from the lateral surfaces 5944 of theinner space portion 594 of the second case 59 at positions spaced fromthe bottom surface 5942 by the same height as the first clinching nuts490 h.

The first clinching nuts 490 h may be fixed to the first case 49 bycaulking or the like. As fastening members 68 are fastened to the firstclinching nuts 490 h in a state in which the fastening holes 590 f ofthe second case 59 are aligned with the first clinching nuts 490 h, thesecond case 59 may be fixed to the first case 49. The fastening members68 serve to firmly fix the second case 59 to the first case 49 whentightened and to allow the second case 59 to be easily separated fromthe first case 49 when loosened.

In addition, a second clinching nut 490 i may be located near an edge ofthe first case 49 opposite to the first clinching nuts 490 h. Inaddition, the second case 59 may have a fastening hole 590 icorresponding to the second clinching nut 490 i and a fastening hole 37i may be formed in the circuit board 37 (or the circuit board unit 300).

The second clinching nut 490 i may be fixed to the first case 49 bycaulking or the like. The second clinching nut 490 i may protrude fromthe bottom surface 4944 to the circuit board 37. As such, the secondclinching nut 490 i serves as a spacer to support the circuit board 37spaced from the first case 49 by a constant distance and, in turn, toimprove fixing stability of the circuit board 37. As the first fasteningmember 62 is fastened to the second clinching nut 490 i in a state inwhich the fastening hole 590 i of the second case 59 and the fasteninghole 37 i of the circuit board 37 are aligned with the second clinchingnut 490 i, the second case 59 and the circuit board 37 may be fixed tothe first case 49. The first fastening member 62 allows the second case59 and the circuit board 37 to be firmly fixed to the first case 49 whentightened and to allow the second case 59 and the circuit board 37 to beeasily separated from the first case 49 when loosened. In addition, thefirst ground structure 72 may be formed by fastening the first fasteningmember 62 through the second clinching nut 490 i and the fastening hole37 i. This will be described below in more detail.

The terminals 31, the bypass diodes 33, the inverter member 35 and thelike are arranged in the case 39. In the embodiment of the invention,the terminals 31, the bypass diodes 33 and the inverter member 35 arelocated together on the circuit board 37 to thereby be integrated withone another by the circuit board 37. As such, in the embodiment of theinvention, the terminals 31 connected to the ribbons 122 and the bypassdiodes 33 are located on the circuit board 37 differently from therelated art.

The circuit board 37 may be a board on which various circuit patterns(for example, wirings, terminals, various connection elements on thecircuit board 37) are formed. The circuit board 37 may have any one ofvarious structures. In one example, a printed circuit board (PCB) may beused as the circuit board 37. The drawing illustrates that all of theterminals 31, the bypass diodes 33, the inverter member 35 and the likeare formed on the single circuit board 37 to achieve a simplifiedstructure. However, the embodiment of the invention is not limitedthereto, and a plurality of circuit boards 37 may be provided andconnected to one another via other circuit boards (for example, flexibleprinted circuit boards (FPCBs)), connectors and the like. Various otheralterations are also possible.

In the embodiment of the invention, the terminals 31 and/or the bypassdiodes 33 are arranged on the circuit board 37. This differs from therelated art in which terminals and bypass diodes are arranged in ajunction box rather than being arranged on a circuit board. When theterminals 31 and/or the bypass diodes 33 are formed on the circuit board37, the terminals 31 and the bypass diodes 33 may be connected to eachother by a circuit pattern of the circuit board 37 and the bypass diodes33 and the inverter member 35 may be connected to each other another bythe circuit pattern of the circuit board 37, which may result in asimplified connection structure. In addition, a metal plate (forexample, a copper plate) forming the circuit board 37 may enhance heatradiation. In particular, since the bypass diodes 33 generate a greatquantity of heat during driving, arranging the bypass diodes 33 on thecircuit board 37 may greatly enhance heat radiation.

The terminals 31 are connected to the ribbons 122 extending from thesolar cells 12 so as to be electrically connected to the solar cellpanel 10. As such, the terminals 31 receive direct current voltage ordirect current generated by the solar cell panel 10 and transmit thesame to the bypass diodes 33 and the inverter member 35.

The terminals 31 connected to the ribbons 122 are located close to oneside of the circuit board 37 (more particularly, one edge of the circuitboard 37 close to the first through-hole 49 a). As the terminals 31connected to the ribbons 122 are located close to the first through-hole49 a, a path of the ribbons 122 is reduced, which may allow the ribbons122 to be easily fixed to the terminals 31. A fixing structure of theribbons 122 and the terminals 31 will be described below in more detailwith reference to FIG. 9. FIG. 9 is a perspective view showing theterminals 31 which may be applied to the integral inverter 30 of thesolar cell module 100 shown in FIG. 1 and the ribbons 122 connected tothe terminals 31.

With reference to FIG. 9, the terminals 31 may be equal in number to theribbons 122 so as to correspond to the ribbons 122 in a one to oneratio. In the embodiment of the invention, the terminals 31 may beconfigured so as to be separably coupled to the ribbons 122. Forexample, in the embodiment of the invention, each of the terminals 31includes upper parts 312 located above the corresponding ribbon 122 anda lower part 314 located below the ribbon 122. The upper part 312 mayinclude a first upper part 312 a fixed to the circuit board 37 at oneside of the ribbon 122 so as to extend from the circuit board 37 to theupper one side of the ribbon 122 and a second upper part 312 b fixed tothe circuit board 37 at the other side of the ribbon 122 so as to extendfrom the circuit board 37 to the other upper side of the ribbon 122, thefirst upper part 312 a and the second upper part 312 b being spacedapart from each other. In addition, the lower part 314 located below thefirst upper part 312 a and the second upper part 312 b is fixed to thecircuit board 37 at a position farther from the first through-hole 49 athan the first and second upper parts 312 a and 312 b so as to extendupward from the circuit board 37 and then extend in parallel to theribbon 122 to thereby cross the first and second upper parts 312 a and312 b. In addition, a portion of the lower part 314 crossing the firstand second upper parts 312 a and 312 b may have a more upwardlyprotruding center portion than both end portions thereof. As such, thecenter portion of the lower part 314 is located closer to the first andsecond upper parts 312 a and 312 b than the end portions.

Once a portion of the lower part 314 fixed to the circuit board 37 ispushed downward to increase a distance between the upper parts 312 andthe lower part 314 of the terminal 31, the ribbon 122 is insertedbetween the upper parts 312 and the lower part 314. Then, upon removalof push force applied to the lower part 314 of the terminal 31, thelower part 314 is moved to the upper parts 312, thus causing the ribbon122 to be fixed between the upper parts 312 (more particularly, thecenter of the upper parts 312) and the lower part 314. In order toseparate the ribbon 122 from the terminal 31, the portion of the lowerpart 314 fixed to the circuit board 37 is again pushed downward toincrease a distance between the upper parts 312 and the lower part 314and then the ribbon 122 is removed.

The upper parts 312 and the lower part 314 of the terminal 31 may befixed to the circuit board 37 via various methods. In one example,portions of the upper parts 312 and the lower part 314 fixed to thecircuit board 37 may have latches (or holding pieces) 312 c and 314 cand holding holes 37 c may be formed in the circuit board 37 atpositions corresponding to the latches 312 c and 314 c. Thereby, as thelatches 312 c and 314 c of the upper parts 312 and the lower part 314are fitted into or released from the holding holes 37 c of the circuitboard 37, the terminal 31 may be easily separated from or coupled to thecircuit board 37. However, the embodiment of the invention is notlimited thereto and the terminal 31 may be fixed to the circuit board 38so as not to be separable and various other alterations are possible.

As a result of the terminal 31 being separably coupled to the ribbon122, the ribbon 122 may be easily separated from the terminal 31 whenrepair, replacement or the like is needed and then, may again be easilyconnected to the terminal 31 as needed. However, the embodiment of theinvention is not limited thereto and the terminal 31 may have variousother structures. In addition, the terminal 31 may be a metal pad, asoldering pad or the like such that the ribbon 122 is bonded to theterminal 31 via welding, soldering or the like. As such, the ribbons 122may be fixed to the terminals 31 so as not to be separable from theterminals 31. This may simplify a structure of the terminal 31 andreduce manufacturing cost of the terminal 31.

With reference again to FIGS. 4 to 6, the bypass diodes 33 connected tothe terminals 31 via the circuit pattern extending from the terminals 31are arranged on the circuit board 37. The bypass diodes 33 are smallerin number than the terminals 31 by one. That is, assuming that thenumber of the terminals 31 is n, the number of the bypass diodes 33 isn−1. Each of the bypass diodes 33 may be located between two terminals31 and connected to the two terminals 31 by the circuit pattern. When aregion where power generation does not occur is formed as a portion ofthe solar cell panel 10 is hidden or due to occurrence of breakdown orthe like, the bypass diodes 33 serve to protect the corresponding regionby causing current to bypass the region. The bypass diodes 33 may haveany one of various known structures.

In addition, the inverter member 35, which is connected to the bypassdiodes 33 by the circuit pattern extending from the bypass diodes 33, isarranged on the circuit board 37. The inverter member 35 serves toconvert direct current (or direct current voltage), supplied from thebypass diodes 33, into alternating current (or alternating currentvoltage). The inverter member 35 may include the DC-AC inverters 352that convert direct current into alternating current and may furtherinclude a current sensors 354, capacitors 356, DC-DC converters 358 andthe like, which are required to stably convert direct current intoalternating current. The current sensors 354, the capacitors 356, theDC-DC converters 358, the DC-AC inverters 352 and the like of theinverter member 35 may be integrated with the terminals 31 and/or thebypass diodes 33 by the circuit board 37 or the circuit pattern formedon the circuit board 37.

The current sensors 354 are connected to the circuit pattern extendingfrom the bypass diodes 33, or connected to the capacitors 356, the DC-DCconverters 358, the DC-AC inverters 352 and the like by the circuitpattern. The current sensors 354 serve to sense whether current from thebypass diodes 33 or from the capacitors 356 is normal, the DC-DCconverters 358, the DC-AC inverters 352 or the like, thereby selectivelystopping operation of the inverter member 35. In the embodiment of theinvention, the bypass diodes 33, the current sensors 354, the capacitors356, the DC-DC converters 358 and the DC-AC inverters 352 may beconnected to one another by the circuit pattern formed on the circuitboard 37 within the same case 39. Such connection between the bypassdiodes 33 and the current sensors 354 eliminates an additional outputcable or the like, resulting in a simplified structure.

In the embodiment of the invention, the current sensors 354 areconnected to the capacitors 356 which store direct current having passedthrough the current sensors 354 and transmit current having constantvoltage to the DC-DC converters 358. Likewise, the current sensors 354and the capacitors 356 may be connected to each other by the circuitpattern formed on the circuit board 37 within the same case 39.

The current having constant voltage from the capacitors 356 may betransmitted to the DC-DC converters 358 to thereby be converted intodirect current having a different value of constant voltage. In theembodiment of the invention, a plurality of DC-DC converters 358 may beprovided. The DC-DC converters 358 enable reduction in a thickness ofeach DC-DC converter 358 as compared to provision of a single DC-DCconverter 358, which may allow a thickness of the integral inverter 30to be less than a height of the extension part 24. However, theembodiment of the invention is not limited thereto and a single DC-DCconverter 358 may be provided.

The direct current or direct current voltage having passed through theDC-DC converters 358 may be transmitted to the DC-AC inverters 352 tothereby be converted into alternating current or alternating currentvoltage. The alternating current or alternating current voltage,generated by the inverter member 35 as described above, is transmittedoutward by the AC output cable 38 that is connected to the integralinverter 30 and passes through the second through-hole 49 b of the case39. For example, the alternating current or alternating current voltagemay be transmitted to another solar cell module 100 via the AC outputcable 38, or may be transmitted to a power grid, a power system or thelike.

The DC-AC inverters 352, the current sensors 354, the capacitors 356 andthe DC-DC converters 358 may have various known structures. In addition,various other components, such as a controller 359 a, a filter 359 b, acommunication unit and the like, may be arranged on the circuit board37. Although the inverter member 35 of the embodiment of the inventionincludes the current sensors 354, the capacitors 356, the DC-DCconverters 358 and the DC-AC inverters 352 arranged in this sequence,the invention is not limited thereto. Thus, positions, connectionrelationships and the like of the current sensors 354, the capacitors356, the DC-DC converters 358 and the DC-AC inverters 352 may be changedin various ways. A connection relationship of the inverter member 35according to another embodiment of the invention will be described belowwith reference to FIGS. 10 and 11.

As shown by example in FIG. 6, the circuit board 37 as well as thebypass diodes 33 and the inverter member 35 arranged on the circuitboard 37 may be enclosed by the potting member 372. In the embodiment ofthe invention, the potting member 372 may be formed to fill the interiorof the inner space portion 594 of the second case 59.

In the embodiment of the invention, the potting member 372 may be formedto cover the bypass diodes 33, the inverter member 35, the circuit board37 and the like while exposing the terminals 31 connected to the ribbons122. When the potting member 372 covers the terminals 31 connected tothe ribbons 122, the potting member 372 may make it difficult todisconnect the ribbons 122 from the terminals 31 upon replacement of thecircuit board unit 300. Therefore, the ribbons 122 may be cut such thatonly portions thereof exposed outward from the potting member 372 areaccessible. This causes reduction in a length of the ribbons 122, thusmaking it difficult for the ribbons 122 to reach the terminals 31 of thecircuit board unit 300 that will be replaced. In addition, when thepotting member 372 is even over the terminals 31 of the circuit boardunit 300 to be replaced, connection of the ribbons 122 to the terminals31 may be impossible.

In consideration of the above-described problem, in the embodiment ofthe invention, the potting member 372 is configured to expose theterminals 31. As such, upon replacement of the circuit board unit 300,the terminals 31 separably coupled to the ribbons 122 may be separatedfrom the ribbons 122. When the terminals 31 are fixed to the ribbons 122via welding or the like, the terminals 31 may be torn away from theribbons 122. In this way, the ribbons 122 may be easily separated fromthe terminals 31 while maintaining an original length thereof. Inaddition, the ribbons 122 may be easily fixed or connected to theexposed terminals 31 of the circuit board unit 300 to be replaced.

In this instance, in the embodiment of the invention, the partitionmember 60 may be provided to separate a first region A1 where theterminals 31 are arranged from a second region A2 where the bypassdiodes 33, the inverter member 35 and the like are arranged. Inaddition, the potting member 372 may be located at the second region A2(or located to cover the second region S2 or to enclose the secondregion A2). Through provision of the partition member 60, even if thepotting member 372 having fluidity is used, it is possible to physicallyprevent the potting member 372 from flowing to the terminals 31 andcovering the terminals 31. As such, the terminals 31 may remaincompletely exposed.

The partition member 60 may be configured to assist the ribbons 122 inbeing easily entering the first region A1 where the terminals 31 arearranged while separating the first region A1 and the second region A2from each other. For example, the partition member 60 may have anopening formed at a position thereof corresponding to a movement path ofthe ribbons 122 for passage of the ribbons 122. Alternatively, a portionor a face of the partition member 60 corresponding to a movement path ofthe ribbons 122 may be removed. The removed portion or face may beunderstood as an opening.

As described above, the terminals 31 of the embodiment of the inventionmay be located near one side of the circuit board 37 close to the firstthrough-hole 49 a. In this instance, the partition member 60 may have anopening at the edge of the circuit board 37 close to the firstthrough-hole 49 a, or a portion of the partition member 60 close to thefirst through-hole 49 a may be removed. This may ensure easy connectionbetween the terminals 31 and the ribbons 122. In addition, the partitionmember 60 may be configured to surround peripheral edges of theterminals 31 except for a peripheral edge corresponding to theabove-described one side of the circuit board 37. In this way, it ispossible to effectively prevent the potting member 372 from entering aportion of the circuit board 37 except for a connection region betweenthe ribbons 122 and the terminals 31.

The partition member 60 may be fixed to the circuit board 37. As such,the partition member 60 may be stably fixed between the terminals 31 andthe bypass diodes 33 and the inverter member 35 with a simplifiedstructure. The partition member 60 may be separably located on thecircuit board 37. For example, the circuit board 37 may have holdingrecesses 37 a and both ends of the partition member 60 adjacent to thecircuit board 37 may be provided with holding pieces 60 a to be caughtby the holding recesses 37 a. Each of the holding pieces 60 a may takethe form of a latch. That is, the holding piece 60 a may have a latchportion 60 b which is gradually increased in width from a narrow endthereof and has a stepped portion from which a width of the holdingpiece 60 a is reduced. As such, when pressure is applied to insert anend of the latch portion 60 b into the holding recess 37 a, the latchportion 60 b having a gradually increasing width passes through theholding recess 37 a until the widest portion of the latch portion 60 bforms the stepped portion to prevent the latch portion 60 b from beingunintentionally separated from the holding recess 37 a. In this way, theholding piece 60 a remains caught by the holding recess 37 a so long asadditional pressure is not applied. Conversely, the holding piece 60 amay be separated from the holding recess 37 a when pressure is appliedto the latch portion 60 b in an opposite direction. With this structure,the partition member 60 may be easily fixed to the circuit board 37 witha simplified structure. In addition, since the holding recess 37 a maybe formed without considerable change in design of the circuit board 37that is used in the related art, it is easy to apply the partitionmember 60 to the circuit board 37. In addition, the circuit board 37 orthe partition member 60 may be easily removed or replaced when defectsare found.

The partition member 60 may include a partition portion 610 extendingperpendicular to the circuit board 37 and a bottom portion 620 locatedat an end of the partition portion 610 adjacent to the circuit board 37,the bottom portion 620 having a greater width than a width of thepartition member 610. The partition portion 610 is not formed at a firstside of the terminals 31 (an upper side of the drawing) adjacent to thefirst through-hole 49 a but formed to connect a second side (a lowerside of the drawing) opposite to the first through-hole 49 a and thirdand fourth sides (left and right sides of the drawing) located atopposite lateral sides of the terminals 31 to each other. As such, thepartition portion 610 may be formed to surround at least threeperipheral edges of the terminals 31. The bottom portion 620 may haveapproximately the same or similar shape as the partition portion 610 andmay have a greater width than a width of the partition portion 610. Thismay maximize a contact area between the partition member 60 and thecircuit board 37 at a portion of the partition member 60 adjacent to thecircuit board 37, thereby preventing the potting member 372 from flowingbetween the partition member 60 and the circuit board 37. In addition,the holding pieces 60 a, caught by the holding recesses 37 a of thecircuit board 37, may extend from the bottom portion 620 to achieveenhanced structural stability.

Portions of the partition member 60 corresponding to the aforementionedthird and fourth sides may be fixed to the lateral surfaces 5944 of thesecond case 59. This may effectively prevent an introduction path of thepotting member 372.

Ends of the partition member 60 adjacent to the first through-hole 49 amay be provided with protrusions 60 c to be fitted into the lateralsurface 5944 of the second case 59. The lateral surfaces 5944 of thesecond case 59 may have insertion recesses 590 c into which theprotrusions 60 c are fitted. The partition member 60 may be fixed to thesecond case 59 as the protrusions 60 c are fitted into the insertionrecesses 590 c. As such, the ends of the partition member 60 adjacent tothe circuit board 37 are fixed to the circuit board 37 by the holdingpieces 60 a and the ends of the partition member 60 adjacent to thefirst through-hole 49 a are fixed to the lateral surfaces 5944 of thesecond case 59 by the protrusions 60 c. Alternatively, an adhesive orthe like may be provided between the protrusions 60 c and the insertionrecesses 590 c. Alternatively, as the potting member 372 adhesivelyfills a gap between the protrusions 60 c and the insertion recesses 590c, the potting member 372 may no longer pass through the gap. Variousother alterations are also possible.

The protrusions 60 c protrude from one side of the circuit board 37adjacent to the first through-hole 49 a and, in other words, protrudefrom the circuit board 37 throughout one side of the circuit board 37adjacent to the first through-hole 49 a, thereby effectively blocking anintroduction path of the potting member 372.

The potting member 372 having fluidity in a liquid state or in a gelstate may be poured into the second region A2 in a state in which thecircuit board unit 300 and the partition member 60 are arranged in thesecond case 59, and then solidified by drying and/or thermal treatmentso as to cover the second region A2. As the potting member 372 isintroduced in a state in which the circuit board unit 300 is located inthe second case 59, the potting member 372 covering the circuit boardunit 300 may be easily formed without an additional mold or the like. Inthis instance, through provision of the partition member 60, the pottingmember 372 is not formed at the first region A1 where the terminals 31are arranged and is formed throughout the second region A2. This allowsthe potting member 372 to cover the bypass diodes 33, the invertermember 35 and the circuit board 37 arranged at the second region A2except for the first region A1.

The above description exemplifies that an upper surface of the circuitboard 37 (i.e. a portion opposite to the bottom surface 5944 of thesecond case 59) is divided into the first region A1 and the secondregion A2 for introduction of the potting member 372 by the partitionmember 60. However, the embodiment of the invention is not limitedthereto and the partition member 60 may be replaced with a portion ofthe second case 59.

For example, a partition portion 5960 may integrally protrude from thebottom surface 5944 of the second case 59 to separate the first region Afrom the second region A2, thereby serving to prevent introduction ofthe potting member 372 into the first region A1. In this instance, thefirst region A1 defined above the circuit board 37 by the partitionmember 60 may have a different planar shape from that of a regiondefined by the partition portion 610 that is formed at the bottomsurface 5944 of the second case 59 and located below the circuit board37. For example, differently from the partition member 60, the partitionportion 5960 of the embodiment of the invention may be shaped toseparate a portion where the terminals 31 are arranged and a portionwhere the capacitors 356 are arranged from the remaining portion. Thisis because a portion where the potting member 372 is not introduced maybe freely designed into a desired shape based on arrangement ofcomponents at upper and lower portions of the circuit board 37. Variousother alterations are also possible.

In the above description, that the potting member 372 covers objectssuch as the bypass diodes 33 and the inverter member 35 includescovering the entirety of the objects, but also includes only coveringsome portions of the objects. That is, in the instance in which thebypass diodes 33, the inverter member 35 and the like have portionsprocessed to exhibit electrical insulation properties, the pottingmember 372 may cover the remaining portions of these components exceptfor the processed portions. For example, the potting member 372 maycover some portions corresponding to the circuit pattern, such aswirings, exposed outward from the bypass diodes 33, the inverter member35 and the like. Thus, it can be appreciated that covering the circuitpattern of the bypass diodes 33 and the inverter member 35 may meanpotting by the potting member 372. In addition, even if at least one ofthe DC-AC inverters 352, the current sensors 354, the capacitors 356 andthe DC-DC converters 358 of the inverter member 35 is covered and pottedby the potting member 372 and the other components are not covered bythe potting member 372, it can be said that the inverter member 35 ispotted by the potting member 372. For example, in some embodiments, thecapacitors 356 and the like may not be potted by the potting member 372.

An inner circuit of the integral inverter 30 (more accurately, astructure of the circuit board unit 300) according to another embodimentof the invention will be described below in detail with reference toFIGS. 10 and 11. FIG. 10 is an example block diagram showing theterminals and the integral inverter of the solar cell module shown inFIG. 1.

With reference to the drawings, the integral inverter 30 may include thebypass diodes 33 (or a bypass diode unit) 33, the DC-DC converter 358(or a converter unit), a capacitor 356, the DC-AC inverter 352 (or aninverter unit), and a controller 359 a.

The bypass diodes 33 may include bypass diodes Da, Db and Dc, which arerespectively arranged between first to fourth conducting lines 135 a,135 b, 135 c and 135 d of the solar cell module 100 formed via theribbons (see reference numeral 122 of FIG. 4) and the terminals (seereference numeral 31 of FIG. 4). In this instance, one or more bypassdiodes may be provided, and the number of the bypass diodes ispreferably smaller than the number of the conducting lines (the numberof the terminals 31 or the number of the ribbons 122) by one.

The bypass diodes Da, Db and Dc receive direct current power, which isgenerated using sunlight, from the solar cell module 100, moreparticularly, from the first to fourth conducting lines 135 a, 135 b,135 c and 135 d of the solar cell module 100. In addition, the bypassdiodes Da, Db and Dc may bypass the direct current power when inversevoltage occurs in the direct current power from at least one of thefirst to fourth conducting lines 135 a, 135 b, 135 c and 135 d.

Meanwhile, input power Vpv having passed through the bypass diodes 33 isinput to the DC-DC converter 358.

The DC-DC converter 358 converts the input power Vpv output from thebypass diodes 33. Meanwhile, the DC-DC converter 358 may be called afirst power converter.

For example, the DC-DC converter 358 may convert the input directcurrent power Vpv into power having pseudo DC voltage. As such, thecapacitor 356 may store power having pseudo DC voltage. Meanwhile, bothends of the capacitor 356 may be called DC terminals and the capacitor356 may be called a DC terminal capacitor. In another example, the DC-DCconverter 358 may boost the input direct current power Vpv to convertthe same into direct current power. As such, the DC terminal capacitor356 may store the boosted direct current power.

The DC-AC inverter 352 may convert the direct current power stored inthe capacitor 356 into alternating current power. Meanwhile, the DC-ACinverter 352 may be called a second power converter.

For example, the DC-AC inverter 352 may convert the power having pseudoDC voltage, converted by the DC-DC converter 358, into alternatingcurrent power. In another example, the DC-AC inverter 352 may convertthe direct current power, boosted by the DC-DC converter 358, intoalternating current power.

Meanwhile, the DC-DC converter 358 preferably includes a plurality ofinterleaving converters for conversion to power having pseudo DC voltageor conversion to power having boosted direct current.

In particular, the embodiment of the invention exemplifies that theDC-DC converter 358 includes three or more interleaving converters.

The drawing shows that n converters 610 a, 610 b, . . . , 610 n areconnected to one another in parallel. The n converters 610 a, 610 b, . .. , 610 n may have the same energy conversion capacity.

The magnitude of the input direct current power Vpv is reduced to 1/N bythe n converters 610 a, 610 b, 610 n, and output current of therespective converters is merged at an output terminal of the nconverters 610 a, 610 b, 610 n.

Meanwhile, the n converters 610 a, 610 b, . . . , 610 n performinterleaving operation, and each of the n converters 610 a, 610 b, . . ., 610 n maintains a current phase of +(360°/N) or −(360°/N) relative toa reference phase or a phase delay close to the current phase.

When the n converters perform interleaving operation as described above,ripples of input current and output current of the DC-DC converter 358are reduced. This advantageously reduces the capacity and size ofcircuit elements in a power conversion module 700.

Meanwhile, as described above, when two interleaving converters areused, a large inductor, a large transformer and the like are required tooutput alternating current power within a range of 290 W to 330 W. Asthe inductor, the transformer and the like are increased in size, it isnecessary to increase a thickness of a junction box and, in turn, athickness of the integral inverter 30 may be greater than a thickness ofthe frame 20 of the solar cell module 100.

To solve the above-described problems, in the embodiment of theinvention, at least three interleaving converters are used. Thereby,smaller sizes of inductor, transformer and the like may be used tooutput the aforementioned alternating current power within a range of290 W to 330 W and, in turn, a thickness of the integral inverter 30 maybe less than a thickness of the frame 20 of the solar cell module 100.

Meanwhile, the interleaving converters may be tapped inductorconverters, flyback converters, or the like.

FIG. 11 is an example circuit diagram of the integral inverter of FIG.10.

With reference to the drawing, the integral inverter 30 may include thebypass diodes 33, the DC-DC converter 358, the capacitor 356, the DC-ACinverter 352, the controller 359 a and the filter 359 b.

FIG. 11 shows a tapped inductor converter as an interleaving converter.In the drawing, the DC-DC converter 358 includes first to third tappedinductor converters 611 a, 611 b and 611 c.

The bypass diodes 33 include first to third bypass diodes Da, Db and Dc,which respectively correspond to the first to fourth conducting lines135 a, 135 b, 135 c and 135 d and are arranged between nodes a, b, c andd.

The DC-DC converter 358 may perform power conversion using directcurrent power Vpv output from the bypass diodes 33.

In particular, the first tapped inductor converter to the third tappedinductor converter 611 a, 611 b and 611 c output direct current power,converted via interleaving operation, to the capacitor 356.

The first tapped inductor converter 611 a includes a tapped inductor T1,a switching element S1 connected between the tapped inductor T1 and aground terminal, and a diode D1 connected to an output terminal of thetapped inductor T1 to perform unidirectional conduction. Meanwhile, thecapacitor 356 is connected between an output terminal of the diode D1,i.e. a cathode and the ground terminal.

More specifically, the switching element S1 may be connected between atap of the tapped inductor T1 and the ground terminal. In addition, anoutput terminal (secondary side) of the tapped inductor T1 is connectedto an anode of the diode D1, and the capacitor 356 is connected betweenthe cathode of the diode D1 and the ground terminal.

Meanwhile, the primary side and the secondary side of the tappedinductor T1 have opposite polarities. Meanwhile, the tapped inductor Tmay be called a transformer.

The primary side and the secondary side of the tapped inductor T1 areconnected to each other as shown in the drawing. As such, the tappedinductor converter may be a non-isolated converter.

Meanwhile, when the three tapped inductor converters 611 a, 611 b and611 c are connected to one another in parallel as shown in the drawingso as to be driven in an interleaving manner, input current is divergedin parallel and, thus, ripples of current output through the respectivetapped inductor converters 611 a, 611 b and 611 c are reduced.

The respective tapped inductor converters 611 a, 611 b and 611 c may beoperated adaptively to correspond to a required value of the outputalternating current power.

For example, when a required power value is within a range ofapproximately 90 W to 130 W, only the first converter 611 a may beoperated. When a required power value is within a range of approximately190 W to 230 W, only the first and second converters 611 a and 611 b maybe operated. When a required power value is within a range ofapproximately 290 W to 330 W, all of the first to third converters 611a, 611 b and 611 c may be operated. That is, the respective tappedinductor converters 611 a, 611 b and 611 c may be selectively operated.This selective operation may be controlled by the controller 359 a.

The DC-AC inverter 352 converts the DC power converted in level by theDC-DC converter 358 into AC power. The drawing illustrates a full bridgeinverter. That is, upper arm switching elements Sa and Sb connected toeach other in series are paired and lower arm switching elements S′a andS′b connected to each other in series are paired, such that two pairs ofupper and lower arm switching elements Sa & S′a and Sb & S′b areconnected to one another in parallel. The respective switching elementsSa, S′a, Sb and S′b are connected to the diodes in anti-parallel.

The switching elements in the DC-AC inverter 352 may be turned on or offbased on an inverter switching control signal from the controller 359 a.Thereby, AC power having a prescribed frequency is output. Preferably,the AC power may have the same frequency as an AC frequency of a grid(for example, approximately 60 Hz or 50 Hz).

The filter 359 b performs low-pass filtering to smooth the AC poweroutput from the DC-AC inverter 352. To this end, the drawing illustratesinductors Lf1 and Lf2, but various other examples are possible.

Meanwhile, a converter input current sensing unit A senses input currentic1 input to the DC-DC converter 358, and a converter input voltagesensing unit B senses input voltage vc1 input to the DC-DC converter358. The sensed input current ic1 and the sensed input voltage vc1 maybe input to the controller 359 a.

A converter output current sensing unit C senses output current ic2output from the DC-DC converter 358, i.e. DC terminal current, and aconverter output voltage sensing unit D senses output voltage vc2 outputfrom the DC-DC converter 358, i.e. DC terminal voltage. The sensedoutput current ic2 and the sensed output voltage vc2 may be input to thecontroller 359 a.

An inverter output current sensing unit E senses current ic3 output fromthe DC-AC inverter 352, and an inverter output voltage sensing unit Fsenses voltage vc3 output from the DC-AC inverter 352. The sensedcurrent ic3 and the sensed voltage vc3 are input to the controller 359a.

The converter input current sensing unit A, the converter input voltagesensing unit B, the converter output current sensing unit C, theconverter output voltage sensing unit D and the inverter output currentsensing unit E may correspond to the current sensors 354 shown in FIG.4.

Meanwhile, the controller 359 a may output a control signal to control aswitching element S1 of the DC-DC converter 358. In particular, thecontroller 359 a may output a turn-on timing signal for the switchingelement S1 in the DC-DC converter 358 based on at least one of thesensed input current ic1, the sensed input voltage vc1, the sensedoutput current ic2, the sensed output voltage vc2, the sensed outputcurrent ic3, or the sensed output voltage vc3.

The controller 359 a may also output an inverter control signal tocontrol the respective switching elements Sa, S′a, Sb and S′b of theDC-AC inverter 352. In particular, the controller 359 a may outputturn-on timing signals of the respective switching elements Sa, S′a, Sband S′b of the DC-AC inverter 352 based on at least one of the sensedinput current ic1, the sensed input voltage vc1, the sensed outputcurrent ic2, the sensed output voltage vc2, the sensed output currentic3 or the sensed output voltage vc3.

Meanwhile, the controller 359 a may calculate the maximum power pointwith respect to the solar cell module 100 and control the DC-DCconverter 358 to output DC power corresponding to the maximum power.

The integral inverter 30 according to the embodiment of the invention inwhich an inner circuit structure is integrated with the bypass diodes 33may be differentiated from the related art in which terminals, bypassdiodes and an inverter member are individually formed.

As described above, in the embodiment of the invention, in a state inwhich the first case part 491 is fixed to the solar cell panel 10, thefirst case part 491 is open to enable repair or replacement of thecircuit board unit 300. This may ensure easy repair and replacement ofthe circuit board unit 300. In addition, the first case 49 may remainbecause the circuit board unit 300 alone may be replaced. Thus, evenwhen the integral inverter 30 breaks, the first case 49 may remain,resulting in reduced repair costs. In particular, when the first case 49is formed of a metal to enhance durability and the like, repair costsmay be greatly reduced.

Hereinafter, a ground structure of the integral inverter 30 according tothe embodiment of the invention will be described below in detail withreference to FIGS. 12A, 12B and 12C. FIGS. 12A, 12B and 12C aresectional views respectively showing the first to third groundstructures 72, 74 and 76 which may be applied to the integral inverter30 shown in FIG. 4. Here, FIG. 12A is a sectional view taken along lineA-A of FIG. 4, FIG. 12B is a sectional view taken along line B-B of FIG.4, and FIG. 12C is a sectional view taken along line C-C of FIG. 4. InFIGS. 12A to 12C, only parts required for description are shown inbrief.

With reference to FIGS. 12A to 12C, in the embodiment of the invention,grounding by the first case 49 may be accomplished via fastening of thefirst to third fastening members 62, 64 and 66. In this instance, thefirst to third fastening members 62, 64 and 66 may comprise a conductivematerial (for example, a metal). The first case 49 may include theconductive material layer 47 and the surface treated layer 48 formed ona surface of the conductive material layer 47. In addition, at least aportion of the surface treated layer 48 where the second and thirdfastening members 64 and 66 to be fastened to the first case 49 arelocated is removed to form a contact portion 48 a at which theconductive material layer 47 is exposed. The second and third fasteningmembers 64 and 66 come into contact with the conductive material layer47 through the contact portion 48 a so as to be electrically connectedto each other, thereby forming a ground structure. This will bedescribed below in more detail.

With reference to FIG. 12A, the first ground structure 72 may includethe second clinching nut 490 i located at the first case 49, thefastening hole 37 i formed in the circuit board 37 at a positioncorresponding to the second clinching nut 490 i, and the first fasteningmember 62 fastened into the clinching nut 490 i through the fasteninghole 37 i. That is, as the first fastening member 62 is fastened throughthe fastening hole 37 i in a state in which the fastening hole 37 i ofthe circuit board 37 is located above the second clinching nut 490 iprotruding from the bottom surface 4942 of the inner space portion 494of the first case 49 toward the circuit board 37, an inner surface ofthe second clinching nut 490 i comes into contact with a threadedportion 62 a of the first fastening member 62, thereby achievinggrounding.

The second clinching nut 490 i may be formed of a conductive materialand be easily electrically connected by the threaded portion 62 a of thefirst fastening member 62 coming into contact with the inner surface ofthe second clinching nut 490 i. In addition, an inner surface of a headportion 62 b of the first fastening member 62 may be connected to thecircuit board 37, a metal plate constituting the circuit board 37, acircuit pattern of the circuit board 37 or the like.

However, the embodiment of the invention is not limited thereto and thesecond clinching nut 490 i may be provided at a surface thereof with thesurface treated layer 48 formed of an electrically insulating materialor the like, similar to the first case part 491 or the second case part492 of the first case 49. Through provision of the surface treated layer48, when the second clinching nut 490 i is fastened to the firstfastening member 62, the surface treated layer 48 formed at the innersurface of the second clinching nut 490 i is removed by the threadedportion 62 a, thus causing the threaded portion 62 a to come intocontact with the conductive material. Alternatively, an additionalprocess of removing the surface treated layer 48 from the inner surfaceof the second clinching nut 490 i before fastening of the firstfastening member 62 may be performed to achieve stable contact betweenthe first fastening member 62 and the conductive material of the secondclinching nut 490 i. Various other alterations are also possible.

When the second clinching nut 490 i and the circuit board 37 areconnected to each other by the first fastening member 62, the circuitboard 37 may be stably grounded to the first case 49. Thereby, thecircuit board 37 having any of various circuit patterns, the bypassdiodes 33, the inverter member 35 and the like may be connected to thefirst case 49 (more accurately, the first case part 491) to form aground passage, thereby maintaining grounding potential of the circuitboard 37.

When the first ground structure 72 is formed by fastening the firstfastening member 62 through the second clinching nut 490 i located atthe first case 49 and the fastening hole 37 i formed in the circuitboard 37, the first ground structure 72 may be formed via a simplifiedstructure and process. In addition, as the first case 49 and the circuitboard 37 are mechanically connected to each other by the first fasteningmember 62, improved fixing stability of the first case 49 and thecircuit board 37 may be accomplished.

With reference to FIG. 12B, the second ground structure 74 may beconfigured by fastening the fastener 49 c of the first case 49 to theframe 20 via the second fastening member 64. That is, the second groundstructure 74 is formed as the second fastening member 64 is fastenedthrough the fastening hole 490 c of the fastener 49 c and the fasteninghole 244 c of the second portion 244 in a state in which the fasteningportion 491 c of the fastener 49 c of the first case 49 comes intocontact with an inner surface of the second portion 244 of the frame 20.In this instance, the frame 20 may be formed of a conductive material toachieve good durability against external shock. In one example, theframe 20 may be formed of a metal or the like.

In this instance, the surface treated layer 48 of the first case 49 isremoved from an inner surface of the fastening hole 490 c in which thesecond fastening member 64 is located to form the contact portion 48 awhere the conductive material layer 47 is exposed. A shape of thecontact portion 48 a will be described below in more detail withreference to FIGS. 13A to 13D.

When the fastening portion 491 c and the second portion 244 are fastenedto each other by the second fastening member 64, a ground path may beformed via connection of the first case 49 (more accurately, the firstcase part 491) and the frame 20. As the circuit board 37 and the firstcase 49 are grounded by the first ground structure 72 and the first case49 and the frame 20 are grounded by the second ground structure 74, aground path may be formed through the circuit board 37, the first case49 and the frame 20. In this way, a simplified ground structure may beaccomplished as constituent elements of the solar cell module 100, i.e.the first case 49, the frame 20 and the like configure a ground path. Inaddition, the frame 20 may be connected to the frame 20 of a neighboringsolar cell module 100 to form a continuous ground structure between theneighboring solar cell modules 100. The frame 20 may be provided with aground line or any of various other ground structures.

The second ground structure 74 may be formed via a simplified structureand process by fastening the fastening portion 491 c to the secondportion 244 using the second fastening member 64. In addition, the firstcase 49 and the frame 20 may be mechanically fixed to each other by thesecond fastening member 64, which may allow the first case 49 to be morefirmly fixed to the solar cell module 100.

However, the embodiment of the invention is not limited thereto and thesecond ground structure 74 may be omitted. For example, when the frame20 comprises no conductive material, the second ground structure 74 isnot provided. Thus, the first case 49 may be provided with a separateground line for grounding. Various other alterations are also possible,

With reference to FIG. 12C, the third ground structure 76 may beconfigured by fastening the extension portions 492 c, 493 c and 494 c ofthe first case part 491 (more particularly, the second extension portion493 c) to the fixture 49 d of the second case part 492 using the thirdfastening member 66. That is, the third ground structure 76 is formed asthe third fastening member 66 is fastened through the fastening hole 490e of the second extension portion 493 c and the fastening hole 490 g ofthe first fixing portion 491 d in a state in which the second extensionportion 493 c of the fastener 49 c of the first case 49 comes intocontact with the fixing portion 491 d of the fixture 49 d.

In this instance, the surface treated layer 48 of the first case 49 isremoved from an inner surface of the fastening holes 490 e and 490 g inwhich the third fastening member 66 is located to form the contactportion 48 a where the conductive material layer 47 is exposed. A shapeof the contact portion 48 a will be described below in more detail withreference to FIGS. 13A to 13D.

When the fastener 49 c and the fixture 49 d are fastened to each otherby the third fastening member 66, a ground path may be formed viaconnection of the first case part 491 and the second case part 492. Asthe circuit board 37 and the first case part 491 are grounded by thefirst ground structure 72, the first case part 491 and the second casepart 492 are grounded by the third ground structure 76 and the firstcase part 491 and the frame 20 are grounded by the second groundstructure 74, a ground path may be formed through the circuit board 37,the first and second case parts 491 and 492 of the first case 49 and theframe 20. In this way, a simplified ground structure may be formedwithout additional elements and the like as constituent elements of thesolar cell module 100, i.e. the first and second case parts 491 and 492of the first case 49, the frame 20 and the like configure a ground path.

The third ground structure 76 may be formed via a simplified structureand process by fastening the fastener 49 c to the fixture 49 d using thethird fastening member 66. In addition, the first case part 491 and thesecond case part 492 may be mechanically fixed to each other by thethird fastening member 66, which may provide more firm fixingtherebetween.

The embodiment of the invention exemplifies that the second case part492 includes the conductive material layer 74 and the surface treatedlayer 48 in the same manner as the first case part 491. When the secondcase part 492 includes the conductive material layer 47 and the surfacetreated layer 48, the first case 49 may achieve enhanced strength andwear-resistance, improved external appearance and the like. However, theembodiment of the invention is not limited thereto, and the first casepart 491 and the second case part 492 may be formed of differentmaterials. For example, the second case part 492 may be formed of anelectrically insulating material, thus having electrical insulationproperties. When the second case part 492 is formed of an electricallyinsulating material, the third ground structure 76 may be omitted.

In the embodiment of the invention, the contact portion 48 a is formedas the surface treated layer 48 of the first case 49 is removed frompositions where the second and third fastening members 64 and 66 arelocated. Various examples related to this formation of the contactportion 48 a will be described below in detail with reference to FIGS.13A to 13D. FIGS. 13A to 13D are views showing various examples of thecontact portion 48 a formed by the third fastening member 66 shown inFIG. 12C. A description related to the contact portion 48 a formed bythe third fastening member 66 with reference to FIG. 13 may be appliedto a description related to the contact portion 48 a formed by thesecond fastening member 64 and the second ground structure 74 formed bythe contact portion 48 a. Thus, a description related to the secondfastening member 64 will be replaced with a description related to thethird fastening member 66 and the second fastening member 64 will not bedescribed below in detail. FIGS. 13A to 13D show a portion correspondingto portion B of FIG. 12C.

As shown by example in FIG. 13A, the contact portion 48 a is formed byremoving a portion of the surface treated layer 48 corresponding to ahead portion 66 b and a threaded portion 66 a of the third fasteningmember 66 so as to expose the conductive material layer 47 adjacent tothe third fastening member 66. In other words, the contact portion 48 amay be formed at the entire inner surfaces of the fastening holes 490 eand 490 f coming into contact with the threaded portion 66 a and at theentire surface of the first case 49 coming into contact with an innersurface of the head portion 66 b. The contact portion 48 a may be formedby performing laser processing, mechanical processing (for example, endmill processing) or the like on the portion corresponding to the headportion 66 b and the threaded portion 66 a of the third fastening member66 prior to fastening the third fastening member 66. When the entirecontact portion 48 a is formed via laser processing or mechanicalprocessing, the third ground structure 76 may be more stably formed.

Alternatively, as shown by example in FIG. 13B, the contact portion 48 amay be formed to partially expose a portion corresponding to the headportion 66 b and the threaded portion 66 a of the third fastening member66. The contact portion 48 a may be formed as the third fastening member66 cuts the surface treated layer 48 of the first case 49 coming intocontact therewith the third fastening member 66 upon fastening throughthe fastening holes 490 e and 490 g. In this instance, the head portion66 b may be provided with ridges P protruding toward the first case 49to effectively remove the surface treated layer 48. The ridges P mayhave any of various shapes. In one example, the ridges P may have any ofvarious shapes, such as a comb pattern, a circular pattern, a starredpattern or the like when viewed in plan.

In one example, the inner surfaces of the fastening holes 490 e and 490g coming into close contact with the threaded portion 66 b of the thirdfastening member 66 may be provided with the contact portion 48 a havinga shape corresponding to the threaded portion 66 b. That is, as thesurface treated layer 48 is removed in a shape corresponding to threadsof the threaded portion 66 b passing through the inner surfaces of thefastening holes 490 e and 490 gt, the contact portion 48 a may beforming into a shape corresponding to the threads. In addition, thecontact portion 48 a may be formed by removing a portion correspondingto the ridges P of the head portion 66 b from a surface of the firstcase 49 coming into close contact with the head portion 66 b of thethird fastening member 66.

When the contact portion 48 a is formed upon fastening of the thirdfastening member 66 as described above, an additional process of formingthe contact portion 48 a is unnecessary, which may result in improvedproductivity.

FIG. 13B shows the ridges P formed at an inner surface of the headportion 66 b. However, the embodiment of the invention is not limitedthereto. In another example, as shown by example in FIG. 13C, a washermember 67 having the ridges P may be further provided between the firstcase 49 and the head portion 66 b to partially expose a portion of thefirst case 49 corresponding to the head portion 66 b of the thirdfastening member 66. The washer member 67 may have a loop shape or anannular shape to define a fastening hole for passage of the thirdfastening member 66, and may be provided with the ridges P at a surfacethereof coming into contact with the first case 49. The ridges P mayhave any of various shapes. In one example, the ridges P may have any ofvarious shapes, such as a comb pattern, a circular pattern, a starredpattern or the like when viewed in plan.

Through provision of the washer member 67, pressure may be moreeffectively applied to the surface treated layer 48 of the first case 49corresponding to the head portion 66 b, which may ensure easierformation of the contact portion 48 a. In addition, a desired shape ofwasher member 67 may be added and easily used in processing.

Alternatively, as shown by example in FIG. 13D, the surface treatedlayer 48 may be removed from part of a portion of the first case 49coming into contact with the threaded portion 66 a of the thirdfastening member 66 to partially form the contact portion 48 a withrespect to the portion corresponding to the threaded portion 66 a andmay be removed from the entire portion of the first case 49 coming intocontact with the head portion 66 b to wholly form the contact portion 48a with respect to the portion corresponding to the head portion 66 b.This serves to improve stability of a ground structure by forming thecontact portion 48 a at a portion corresponding to the head portion 66 bprior to fastening of the fastening member 66 and to improveproductivity by forming the contact portion 48 a at the inner surfacesof the fastening holes 490 e and 490 g upon fastening of the fasteningmember in consideration of the fact that the fastening holes 490 e and490 g are generally small and have difficulty in removing the surfacetreated layer 48 therefrom. In another example, the contact portion 48 ais formed at part of a portion corresponding to the head portion 66 band is formed at the entire portion corresponding to the threadedportion 66 a. Various other alterations are also possible.

Although the embodiment of the invention exemplifies that the firstground structure 72 is formed via connection of the circuit board 37 andthe first case part 491, the embodiment of the invention is not limitedthereto. Thus, the first ground structure 72 may be formed viaconnection of the circuit board 37 and the second case part 492. Variousother alterations are also possible.

In the integral inverter 30 of the solar cell module 100 having theabove described structure, the terminals 31 connected to the ribbons 122and/or the bypass diodes 33 that provide a bypass path and the invertermember 35 that converts direct current into alternating current areintegrated with each other. This integration may result in a simplifiedinstallation process and a simplified structure. In addition, as thebypass diodes 33 and the inverter member 35 are connected to each othervia the circuit pattern, output cables (i.e. DC output cables) forconnection between the bypass diodes 33 and the inverter member 35 maybe omitted, which may result in a simplified structure and preventdamage to the solar cell panel 10 caused by the output cables.

On the other hand, in the related art, a junction box and an invertermust be individually manufactured and fixed to a solar cell panel orframe and, thereafter, a positive output cable and a negative outputcable of the junction box must be connected to the inverter. Inaddition, there is an AC output cable of the inverter. This may increasean installation space and installation time and cause damage to orbreakdown of the solar cell panel 10 because the three output cablesapply shock to the solar cell panel 10 during transportation or when inuse.

In the embodiment of the invention, additionally, since the circuitboard unit 300 is separable from the first case 49, easy repair andreplacement of the circuit board unit 300 is possible, which may enhancerepair and replacement efficiency of the integral inverter 30 andminimize replacement costs thereof. In the embodiment of the invention,the first ground structure 72 of the integral inverter 30 is configuredusing the first case 49 of the integral inverter 30, which may simplifya ground structure while achieving reliability of the circuit board 37and, in turn, improve stability of the integral inverter 30. In thisinstance, grounding the first case 49 and the frame 20 by the secondground structure 74 may provide a sufficient ground path to simplify aground structure. In addition, when the first case 49 includes the firstand second case parts 491 and 492 to allow the circuit board unit 300 tobe easily located in the first case 49, the first case 49 and thecircuit board unit 300 may be grounded by the third ground structure 74,which may further improve electrical stability of the integral inverter30. This may minimize accidents, such as electrical short, electricshock and the like.

The above described features, configurations, effects, and the like areincluded in at least one of the embodiments of the invention, and shouldnot be limited to only one embodiment. In addition, the features,configurations, effects, and the like as illustrated in each embodimentmay be implemented with regard to other embodiments as they are combinedwith one another or modified by those skilled in the art. Thus, contentrelated to these combinations and modifications should be construed asincluding in the scope and spirit of the embodiments of the invention asdisclosed in the accompanying claims.

What is claimed:
 1. An integral inverter usable with a solar cell modulecomprising a solar cell panel, the integral inverter comprising: aterminal connected to a ribbon extended from the solar cell panel forinputting a DC power from the solar cell panel; a bypass diodeelectrically connected to the terminal; an inverter member including adirect current (DC)-alternating current (AC) inverter electricallyconnected to the bypass diode; a case configured to integrate theterminal and the bypass diode with the DC-AC inverter located therein,wherein the terminal, the bypass diode and the DC-AC inverter are formedon a circuit board or another circuit board so as to be integrated witheach other, and the case including a conductive metal and serving as aground; an inner case located in the case and receiving the circuitboard or the another circuit board, and the inner case including anelectrically insulating material to maintain an electrical insulationdistance between the case and the circuit board or the another circuitboard; and a single AC cable for outputting AC power from the case,wherein the terminal is connected to the inverter member without a DCoutput cable, wherein the case includes a bottom surface adjacent to aback surface of the solar cell panel and having an opening through whichthe ribbon is passed, wherein the bottom surface of the case is adheredto the back surface of the solar cell panel by an adhesive membercircumferentially surrounding the opening to define a closed spacebetween the case and the back surface of the solar cell panel, andwherein another part of the case is fixed to a frame of the solar cellpanel to form a ground structure.
 2. The integral inverter according toclaim 1, wherein the inverter member further includes direct current(DC)-direct current (DC) converters, and wherein the direct current(DC)-direct current (DC) converters are connected to one another inparallel.
 3. The integral inverter according to claim 1, wherein thecase further comprises a fixture fixed to the frame of the solar cellpanel.
 4. The integral inverter according to claim 1, wherein theterminal, the bypass diode and the DC-AC inverter on the circuit boardor the another circuit board are surrounded by a potting member so as tobe integrated with each other by the potting member.
 5. The integralinverter according to claim 1, wherein the single AC output cable isconfigured to outwardly transmit alternating current converted by theintegral inverter.
 6. The integral inverter according to claim 1,wherein the case receives the terminal, the bypass diode and the DC-ACinverter therein, and wherein the case further includes a through-holefor the single AC output cable.
 7. The integral inverter according toclaim 6, wherein a potting member surrounding the circuit board or theanother circuit board, the bypass diode, and the DC-AC inverter arelocated in the inner case.
 8. The integral inverter according to claim1, wherein the case and the inner case are fixed to each other by afixing member.
 9. The integral inverter according to claim 8, whereinthe fixing member includes at least one of a bonding member, an elasticmember, a latch member or a fastening member.
 10. The integral inverteraccording to claim 8, wherein the inner case includes a first portionand a second portion separated from the first portion.
 11. The integralinverter according to claim 1, further comprising at least one of: afirst ground structure configured to ground the case and the circuitboard or the another circuit board; a second ground structure configuredto ground the case and the frame of the solar cell panel; and a thirdground structure configured to ground the case and the inner casecoupled to the case.
 12. The integral inverter according to claim 11,wherein at least one of the first to third ground structures is groundedvia fastening of a fastening member.
 13. The integral inverter accordingto claim 1, wherein the circuit board integrating the terminal, thebypass diode and the DC-AC inverter is entirely enclosed within oneinner space portion formed in the case.
 14. The integral inverteraccording to claim 1, wherein the ribbon extends perpendicularly to thebottom surface of the case through the opening.
 15. The integralinverter according to claim 1, wherein the adhesive member provides aspacing between the bottom surface of the case and the back surface ofthe solar cell panel.